














	 Athena Widget Set -- C Language Interface

		      X Window System

		 X Version 11, Release 6.4







		     Chris D. Peterson
		 formerly MIT X Consortium





















































X Window System is a trademark of X Consortium, Inc.

Copyright (C) 1985, 1986, 1987, 1988, 1989, 1991, 1994 X
Consortium

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documenta-
tion files (the ``Software''), to deal in the Software with-
out restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to
whom the Software is furnished to do so, subject to the fol-
lowing conditions:

The above copyright notice and this permission notice shall
be included in all copies or substantial portions of the
Software.

THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY
KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PUR-
POSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE X CONSOR-
TIUM BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
OR OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of the X Con-
sortium shall not be used in advertising or otherwise to
promote the sale, use or other dealings in this Software
without prior written authorization from the X Consortium.

Copyright (C) 1985, 1986, 1987, 1988, 1989, 1991 Digital
Equipment Corporation, Maynard, Massachusetts.

Permission to use, copy, modify and distribute this documen-
tation for any purpose and without fee is hereby granted,
provided that the above copyright notice appears in all
copies and that both that copyright notice and this permis-
sion notice appear in supporting documentation, and that the
name of Digital not be used in in advertising or publicity
pertaining to distribution of the software without specific,
written prior permission.  Digital makes no representations
about the suitability of the software described herein for












any purpose.  It is provided ``as is'' without express or
implied warranty.

































































		      Acknowledgments



Many thanks go to Ralph Swick (Project Athena / Digital) who
has contributed much time and effort to this widget set.
Previous versions of the widget set are largely due to his
time and effort.  Many of the improvements that I have been
able to make are because he provided a solid foundation to
build upon.  While much of the effort has been Ralph's, many
other people have contributed to the code.


     Mark Ackerman (formerly Project Athena)
     Donna Converse (MIT X Consortium)
     Jim Fulton (formerly MIT X Consortium)
     Loretta Guarino-Reid (Digital WSL)
     Charles Haynes (Digital WSL)
     Rich Hyde (Digital WSL)
     Mary Larson (Digital UEG)
     Joel McCormack (Digital WSL)
     Ron Newman (formerly Project Athena)
     Jeanne Rich (Digital WSL)
     Terry Weissman (formerly Digital WSL)


While not much remains of the X10 toolkit, many of the ideas
for this widget set come from that original version.  The
design and implementation of the X10 toolkit were done by:


     Mike Gancarz (formerly Digital UEG)
     Charles Haynes (Digital WSL)
     Phil Karlton (formerly Digital WSL)
     Kathleen Langone (Digital UEG)
     Mary Larson (Digital UEG)
     Ram Rao (Digital UEG)
     Smokey Wallace (formerly Digital WSL)
     Terry Weissman (formerly Digital WSL)


I have used the formatting ideas, and some of the words from
previous versions of this document.  The X11R3 Athena widget
document was written by:


     Ralph R. Swick (Project Athena/ Digital)
     Terry Weissman (formerly Digital WSL)
     Al Mento (Digital UEG)


Putting this manual together was a major task in and of
itself.  I would like to thank Ralph Swick, Donna Converse,



			      v








and Jim Fulton for taking the time to help convert my tech-
nical knowledge into legible text.  A special thanks to Jean
Diaz (O'Reilly and Associates) for spending nearly a month
with me working out all the annoying little details.


Chris D. Peterson
MIT X Consortium 1989



The R5 edition of this document has been edited by the
research staff of the MIT X Consortium, with significant
contributions by Jim Fulton (NCD).


Donna Converse
MIT X Consortium 1991



The R6 edition of this document has been edited to reflect
changes brought about by research staff of the Omron Corpo-
ration, with special recognition to Li Yuhong, Seiji Kuwari,
and Hiroshi Kuribayashi for the X11R5/contrib/lib/Xaw inter-
nationalization that inspired this version.


Frank Sheeran
Omron Corporation 1994



























			     vi










			 Chapter 1

	     Athena Widgets and The Intrinsics



The X Toolkit is made up of two distinct pieces, the Xt
Intrinsics and a widget set.  The Athena widget set is a
sample implementation of a widget set built upon the Intrin-
sics.  In the X Toolkit, a widget is the combination of an X
window or subwindow and its associated input and output
semantics.

Because the Intrinsics provide the same basic functionality
to all widget sets it may be possible to use widgets from
the Athena widget set with other widget sets based upon the
Intrinsics.  Since widget sets may also implement private
protocols, all functionality may not be available when mix-
ing and matching widget sets.  For information about the
Intrinsics, see the X Toolkit Intrinsics -- C Language
Interface.

The Athena widget set is a library package layered on top of
the Intrinsics and Xlib that provides a set of user inter-
face tools sufficient to build a wide variety of applica-
tions.	This layer extends the basic abstractions provided
by X and provides the next layer of functionality primarily
by supplying a cohesive set of sample widgets.	Although the
Intrinsics are a Consortium standard, there is no standard
widget set.

To the extent possible, the Intrinsics are "policy-free".
The application environment and widget set, not the Intrin-
sics, define, implement, and enforce:

o    Policy

o    Consistency

o    Style

Each individual widget implementation defines its own pol-
icy.  The X Toolkit design allows for, but does not neces-
sarily encourage, the free mixing of radically differing
widget implementations.

1.1.  Introduction to the X Toolkit

The X Toolkit provides tools that simplify the design of
application user interfaces in the X Window System program-
ming environment.  It assists application programmers by
providing a set of common underlying user-interface



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Athena Widget Set			    X11, Release 6.4


functions.  It also lets widget programmers modify existing
widgets, by subclassing, or add new widgets.  By using the X
Toolkit in their applications, programmers can present a
similar user interface across applications to all worksta-
tion users.

The X Toolkit consists of:

o    A set of Intrinsics functions for building widgets

o    An architectural model for constructing widgets

o    A widget set for application programming

While the majority of the Intrinsics functions are intended
for the widget programmer, a subset of the Intrinsics func-
tions are to be used by application programmers (see  X
Toolkit Intrinsics -- C Language Interface).  The architec-
tural model lets the widget programmer design new widgets by
using the Intrinsics and by combining other widgets.  The
application interface layers built on top of the X Toolkit
include a coordinated set of widgets and composition poli-
cies.  Some of these widgets and policies are specific to a
single application domain, and others are common to a vari-
ety of applications.

The remainder of this chapter discusses the X Toolkit and
Athena widget set:

o    Terminology

o    Model

o    Conventions used in this manual

o    Format of the Widget Reference Chapters

1.2.  Terminology


In addition to the terms already defined for X programming
(see Xlib -- C Language X Interface), the following terms
are specific to the Intrinsics and Athena widget set and
used throughout this document.

Application programmer

     A programmer who uses the X Toolkit to produce an
     application user interface.

Child

     A widget that is contained within another "parent" wid-
     get.



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Athena Widget Set			    X11, Release 6.4


Class

     The general group to which a specific object belongs.

Client

     A function that uses a widget in an application or for
     composing other widgets.

FullName

     The name of a widget instance appended to the full name
     of its parent.

Instance

     A specific widget object as opposed to a general widget
     class.

Method

     A function or procedure implemented by a widget class.

Name

     The name that is specific to an instance of a widget
     for a given client.  This name is specified at creation
     time and cannot be modified.

Object

     A data abstraction consisting of private data and pri-
     vate and public functions that operate on the private
     data.  Users of the abstraction can interact with the
     object only through calls to the object's public func-
     tions.  In the X Toolkit, some of the object's public
     functions are called directly by the application, while
     others are called indirectly when the application calls
     the common Intrinsics functions.  In general, if a
     function is common to all widgets, an application uses
     a single Intrinsics function to invoke the function for
     all types of widgets.  If a function is unique to a
     single widget type, the widget exports the function.

Parent

     A widget that contains at least one other ("child")
     widget.  A parent widget is also known as a composite
     widget.

Resource

     A named piece of data in a widget that can be set by a
     client, by an application, or by user defaults.



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Athena Widget Set			    X11, Release 6.4


Superclass

     A larger class of which a specific class is a member.
     All members of a class are also members of the super-
     class.

User

     A person interacting with a workstation.

Widget

     An object providing a user-interface abstraction (for
     example, a Scrollbar widget).

Widget class

     The general group to which a specific widget belongs,
     otherwise known as the type of the widget.

Widget programmer

     A programmer who adds new widgets to the X Toolkit.

1.3.  Underlying Model

The underlying architectural model is based on the following
premises:

Widgets are X windows

     Every user-interface widget is associated with an X
     window.  The X window ID for a widget is readily avail-
     able from the widget.  Standard Xlib calls can be used
     by widgets for many of their input and output opera-
     tions.

Information hiding

     The data for every widget is private to the widget and
     its subclasses.  That is, the data is neither directly
     accessible nor visible outside of the module implement-
     ing the widget.  All program interaction with the wid-
     get is performed by a set of operations (methods) that
     are defined for the widget.












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Athena Widget Set			    X11, Release 6.4


Widget semantics and widget layout geometry

     Widget semantics are clearly separated from widget lay-
     out geometry.  Widgets are concerned with implementing
     specific user-interface semantics.  They have little
     control over issues such as their size or placement
     relative to other widget peers.  Mechanisms are pro-
     vided for associating geometric managers with widgets
     and for widgets to make suggestions about their own
     geometry.

1.4.  Conventions Used in this Manual

o    All resources available to the widgets are listed with
     each widget.  Many of these are available to more than
     one widget class due to the object oriented nature of
     the Intrinsics.  The new resources for each widget are
     listed in bold text, and the inherited resources are
     listed in plain text.

o    Global symbols are printed in bold and can be function
     names, symbols defined in include files, or structure
     names.  Arguments are printed in italics.

o    Each function is introduced by a general discussion
     that distinguishes it from other functions.  The func-
     tion declaration itself follows, and each argument is
     specifically explained.  General discussion of the
     function, if any is required, follows the arguments.
     Where applicable, the last paragraph of the explanation
     lists the return values of the function.

o    To eliminate any ambiguity between those arguments that
     you pass and those that a function returns to you, the
     explanations for all arguments that you pass start with
     the word specifies or, in the case of multiple argu-
     ments, the word specify. The explanations for all argu-
     ments that are returned to you start with the word
     returns or, in the case of multiple arguments, the word
     return.  The explanations for all arguments that you
     can pass and are returned start with the words speci-
     fies and returns.

o    Any pointer to a structure that is used to return a
     value is designated as such by the _return suffix as
     part of its name.	All other pointers passed to these
     functions are used for reading only.  A few arguments
     use pointers to structures that are used for both input
     and output and are indicated by using the _in_out suf-
     fix.







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Athena Widget Set			    X11, Release 6.4


1.5.  Format of the Widget Reference Chapters

The majority of this document is a reference guide for the
Athena widget set.  Chapters three through six give the pro-
grammer all information necessary to use the widgets.  The
layout of the chapters follows a specific pattern to allow
the programmer to easily find the desired information.

The first few pages of every chapter give an overview of the
widgets in that section.  Widgets are grouped into chapters
by functionality.

Chapter 3
       Simple Widgets

Chapter 4
       Menus

Chapter 5
       Text Widgets

Chapter 6
       Composite and Constraint Widget

Following the introduction will be a description of each
widget in that chapter.  When no functional grouping is
obvious the widgets are listed in alphabetical order, such
as in chapters three and six.

The first section of each widget's description is a table
that contains general information about this widget class.
Here is the table for the Box widget, and an explanation of
all the entries.


Application Header file<X11/Xaw/Box.h>
Class Header file   <X11/Xaw/BoxP.h>
Class		    boxWidgetClass
Class Name	    Box
Superclass	    Composite



Application Header File
		    This file must be included when an
		    application uses this widget.  It usu-
		    ally contains the class definition, and
		    some resource macros.  This is often
		    called the ``public'' header file.

Class Header File   This file will only be used by widget
		    programmers.  It will need to be
		    included by any widget that subclasses
		    this widget.  This is often called the



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Athena Widget Set			    X11, Release 6.4


		    ``private'' header file.

Class		    This is the widget class of this widget.
		    This global symbol is passed to XtCre-
		    ateWidget so that the Intrinsics will
		    know which type of widget to create.

Class Name	    This is the resource name of this class.
		    This name can be used in a resource file
		    to match any widget of this class.

Superclass	    This is the superclass that this widget
		    class is descended from.  If you under-
		    stand how the superclass works it will
		    allow you to more quickly understand
		    what this widget does, since much of its
		    functionality may be inherited from its
		    superclass.


After this table follows a general description of the
default behavior of this widget, as seen by the user.  In
many cases this functionality may be overridden by the
application programmer, or by the user.

The next section is a table showing the name, class, type
and default value of each resource that is available to this
widget.  There is also a column containing notes describing
special restrictions placed upon individual resources.

A    This resource may be automatically adjusted when
     another resource is changed.

C    This resource is only settable at widget creation time,
     and may not be modified with XtSetValues.

D    Do not modify this resource.  While setting this
     resource will work, it can cause unexpected behavior.
     When this symbol appears there is another, preferred,
     interface provided by the X Toolkit.

R    This resource is READ-ONLY, and may not be modified.

After the resource table is a detailed description of every
resource available to that widget.  Many of these are redun-
dant, but printing them with each widget saves page flip-
ping.  The names of the resources that are inherited are
printed in plain text, while the names of the resources that
are new to this class are printed in bold.  If you have
already read the description of the superclass you need only
pay attention to the resources printed in bold.

For each composite widget there is a section on layout
semantics that follows the resource description.  This



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Athena Widget Set			    X11, Release 6.4


section will describe the effect of constraint resources on
the layout of the children, as well as a general description
of where it prefers to place its children.

Descriptions of default translations and action routines
come next, for widgets to which they apply.  The last item
in each widget's documentation is the description of all
convenience routines provided by the widget.

1.6.  Input Focus

The Intrinsics define a resource on all Shell widgets that
interact with the window manager called input.	This
resource requests the assistance of window manager in
acquiring the input focus.  The resource defaults to False
in the Intrinsics, but is redefined to default to True when
an application is using the Athena widget set.	An applica-
tion programmer may override this default and set the
resource back to False if the application does not need the
window manager to give it the input focus.  See the X
Toolkit Intrinsics -- C Language Interface for details on
the input resource.



































			      8





Athena Widget Set			    X11, Release 6.4




			 Chapter 2

		       Using Widgets



Widgets serve as the primary tools for building a user
interface or application environment.  The Athena widget set
consists of primitive widgets that contain no children (for
example, a command button) and composite widgets which may
contain one or more widget children (for example, a Box wid-
get).

The remaining chapters explain the widgets that are provided
by the Athena widget set.  These user-interface components
serve as an interface for application programmers who do not
want to implement their own widgets.  In addition, they
serve as a starting point for those widget programmers who,
using the Intrinsics mechanisms, want to implement alterna-
tive application programming interfaces.

This chapter is a brief introduction to widget programming.
The examples provided use the Athena widgets, though most of
the concepts will apply to all widget sets.  Although there
are several programming interfaces to the X Toolkit, only
one is described here.	A full description of the program-
ming interface is provided in the document X Toolkit Intrin-
sics -- C Language Interface.

2.1.  Setting the Locale

If it is desirable that the application take advantage of
internationalization (i18n), you must establish locale with
XtSetLanguageProc before XtDisplayInitialize or XtAppIni-
tialize is called.  For full details, please refer to the
document X Toolkit Intrinsics -- C Language Interface, sec-
tion 2.2. However, the following simplest-case call is suf-
ficient in many or most applications.


	  XtSetLanguageProc(NULL, NULL, NULL);


Most notably, this will affect the Standard C locale, deter-
mine which resource files will be loaded, and what fonts
will be required of FontSet specifications.  In many cases,
the addition of this line is the only source change required
to internationalize Xaw programs, and will not disturb the
function of programs in the default "C" locale.






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Athena Widget Set			    X11, Release 6.4


2.2.  Initializing the Toolkit

You must call a toolkit initialization function before
invoking any other toolkit routines (besides locale setting,
above).  XtAppInitialize opens the X server connection,
parses the command line, and creates an initial widget that
will serve as the root of a tree of widgets created by this
application.

Widget XtAppInitialize(app_context_return, application_class, options, num_options,
		    argc_in_out, argv_in_out, fallback_resources, args, num_args)
      XtAppContext *app_context_return;
      String application_class;
      XrmOptionDescRec options[];
      Cardinal num_options;
      int *argc_in_out;
      String *argv_in_out[];
      String *fallback_resources;
      ArgList args;
      Cardinal num_args;


app_con_return Returns the application context of this
	       application, if non-NULL.

application_class
	       Specifies the class name of this application,
	       which is usually the generic name for all
	       instances of this application.  A useful con-
	       vention is to form the class name by capital-
	       izing the first letter of the application
	       name. For example, the application named
	       ``xman'' has a class name of ``Xman''.

options        Specifies how to parse the command line for
	       any application-specific resources.  The
	       options argument is passed as a parameter to
	       XrmParseCommand.  For further information,
	       see Xlib -- C Language X Interface.

num_options    Specifies the number of entries in the
	       options list.

argc_in_out    Specifies a pointer to the number of command
	       line parameters.

argv_in_out    Specifies the command line parameters.

fallback_resources
	       Specifies resource values to be used if the
	       site-wide application class defaults file
	       cannot be opened, or NULL.





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Athena Widget Set			    X11, Release 6.4


args	       Specifies the argument list to use when cre-
	       ating the Application shell.

num_args       Specifies the number of arguments in args.

This function will remove the command line arguments that
the toolkit reads from argc_in_out, and argv_in_out.  It
will then attempt to open the display.	If the display can-
not be opened, an error message is issued and XtAppInitial-
ize terminates the application.  Once the display is opened,
all resources are read from the locations specified by the
Intrinsics.  This function returns an ApplicationShell wid-
get to be used as the root of the application's widget tree.

2.3.  Creating a Widget

Creating a widget is a three-step process.  First, the wid-
get instance is allocated, and various instance-specific
attributes are set by using XtCreateWidget.  Second, the
widget's parent is informed of the new child by using XtMan-
ageChild.  Finally, X windows are created for the parent and
all its children by using XtRealizeWidget and specifying the
top-most widget. The first two steps can be combined by
using XtCreateManagedWidget.  In addition, XtRealizeWidget
is automatically called when the child becomes managed if
the parent is already realized.

To allocate, initialize, and manage a widget, use
XtCreateManagedWidget.

Widget XtCreateManagedWidget(name, widget_class, parent, args, num_args)
      String name;
      WidgetClass widget_class;
      Widget parent;
      ArgList args;
      Cardinal num_args;


name	  Specifies the instance name for the created widget
	  that is used for retrieving widget resources.

widget_class
	  Specifies the widget class pointer for the created
	  widget.

parent	  Specifies the parent widget ID.

args	  Specifies the argument list.	The argument list is
	  a variable-length list composed of name and value
	  pairs that contain information pertaining to the
	  specific widget instance being created.  For fur-
	  ther information, see Section 2.7.2.





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Athena Widget Set			    X11, Release 6.4


num_args  Specifies the number of arguments in the argument
	  list.  If the num_args is zero, the argument list
	  is never referenced.

When a widget instance is successfully created, the widget
identifier is returned to the application.  If an error is
encountered, the XtError routine is invoked to inform the
user of the error.

For further information, see X Toolkit Intrinsics -- C Lan-
guage Interface.

2.4.  Common Resources

Although a widget can have unique arguments that it under-
stands, all widgets have common arguments that provide some
regularity of operation.  The common arguments allow arbi-
trary widgets to be managed by higher-level components with-
out regard for the individual widget type.  Widgets will
ignore any argument that they do not understand.

The following resources are retrieved from the argument list
or from the resource database by all of the Athena widgets:

--------------------------------------------------------------------------------
Name		    Class		Type		   Default Value
--------------------------------------------------------------------------------
accelerators	    Accelerators	AcceleratorTable   NULL
ancestorSensitive   AncestorSensitive	Boolean 	   True
background	    Background		Pixel		   XtDefaultBackground
backgroundPixmap    Pixmap		Pixmap		   XtUnspecifiedPixmap
borderColor	    BorderColor 	Pixel		   XtDefaultForeground
borderPixmap	    Pixmap		Pixmap		   XtUnspecifiedPixmap
borderWidth	    BorderWidth 	Dimension	   1
colormap	    Colormap		Colormap	   Parent's Colormap
depth		    Depth		int		   Parent's Depth
destroyCallback     Callback		XtCallbackList	   NULL
height		    Height		Dimension	   widget dependent
mappedWhenManaged   MappedWhenManaged	Boolean 	   True
screen		    Screen		Screen		   Parent's Screen
sensitive	    Sensitive		Boolean 	   True
translations	    Translations	TranslationTable   widget dependent
width		    Width		Dimension	   widget dependent
x		    Position		Position	   0
y		    Position		Position	   0
--------------------------------------------------------------------------------


The following additional resources are retrieved from the
argument list or from the resource database by many of the
Athena widgets:






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Athena Widget Set			    X11, Release 6.4


------------------------------------------------------------------------
Name		    Class	  Type		   Default Value
------------------------------------------------------------------------
callback	    Callback	  XtCallbackList   NULL
cursor		    Cursor	  Cursor	   widget dependent
foreground	    Foreground	  Pixel 	   XtDefaultForeground
insensitiveBorder   Insensitive   Pixmap	   GreyPixmap
------------------------------------------------------------------------


2.5.  Resource Conversions

Most resources in the Athena widget set have a converter
registered that will translate the string in a resource file
to the correct internal representation.  While some are
obvious (string to integer, for example), others need spe-
cific mention of the allowable values.	Three general con-
verters are described here:

o    Cursor

o    Pixel

o    Bitmap

Many widgets have defined special converters that apply only
to that widget.  When these occur, the documentation section
for that widget will describe the converter.

2.5.1.	Cursor Conversion

The value for the cursorName resource is specified in the
resource database as a string, and is of the following
forms:

o    A standard X cursor name from < X11/cursorfont.h >.
     The names in cursorfont.h each describe a specific cur-
     sor.  The resource names for these cursors are exactly
     like the names in this file except the XC_ is not used.
     The cursor definition XC_gumby has a resource name of
     gumby.

o    Glyphs, as in FONT font-name glyph-index [[ font-name ]
     glyph-index ].  The first font and glyph specify the
     cursor source pixmap.  The second font and glyph spec-
     ify the cursor mask pixmap.  The mask font defaults to
     the source font, and the mask glyph index defaults to
     the source glyph index.

o    A relative or absolute file name.	If a relative or
     absolute file name is specified, that file is used to
     create the source pixmap.	Then the string "Mask" is
     appended to locate the cursor mask pixmap.  If the
     "Mask" file does not exist, the suffix "msk" is tried.



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Athena Widget Set			    X11, Release 6.4


     If "msk" fails, no cursor mask will be used.  If the
     filename does not start with '/' or './' the the bitmap
     file path is used (see section 2.4.3).

2.5.2.	Pixel Conversion

The string-to-pixel converter takes any name that is accept-
able to XParseColor (see Xlib -- C Language X Interface).
In addition this routine understands the special toolkit
symbols `XtDefaultForeground' and `XtDefaultBackground',
described in X Toolkit Intrinsics -- C Language Interface.
In short the acceptable pixel names are:

o    Any color name for the rgb.txt file (typically in the
     directory /usr/lib/X11 on POSIX systems).

o    A numeric specification of the form #<red><green><blue>
     where these numeric values are hexadecimal digits (both
     upper and lower case).

o    The special strings `XtDefaultForeground' and `XtDe-
     faultBackground'

2.5.3.	Bitmap Conversion

The string-to-bitmap converter attempts to locate a file
containing bitmap data whose name is specified by the input
string.  If the file name is relative (i.e. does not begin
with / or ./), the directories to be searched are specified
in the bitmapFilePath resource--class BitmapFilePath.  This
resource specifies a colon (:) separated list of directories
that will be searched for the named bitmap or cursor glyph
(see section 2.4.1).  The bitmapFilePath resource is global
to the application, and may not be specified differently for
each widget that wishes to convert a cursor to bitmap.	In
addition to the directories specified in the bitmapFilePath
resource a default directory is searched.  When using POSIX
the default directory is /usr/include/X11/bitmaps.

2.6.  Realizing a Widget

The XtRealizeWidget function performs two tasks:

o    Calculates the geometry constraints of all managed
     descendants of this widget.  The actual calculation is
     put off until realize time for performance reasons.

o    Creates an X window for the widget and, if it is a com-
     posite widget, realizes each of its managed children.

void XtRealizeWidget(w)
      Widget w;





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Athena Widget Set			    X11, Release 6.4


w	  Specifies the widget.

For further information about this function, see the X
Toolkit Intrinsics -- C Language Interface.

2.7.  Processing Events

Now that the application has created, managed and realized
its widgets, it is ready to process the events that will be
delivered by the X Server to this client.  A function call
that will process the events is XtAppMainLoop.

void XtAppMainLoop(app_context)
      XtAppContext app_context;


app_context
	  Specifies the application context of this applica-
	  tion.  The value is normally returned by XtAppIni-
	  tialize.

This function never returns: it is an infinite loop that
processes the X events.  User input can be handled through
callback procedures and application defined action routines.
More details are provided in X Toolkit Intrinsics -- C Lan-
guage Interface.

2.8.  Standard Widget Manipulation Functions

After a widget has been created, a client can interact with
that widget by calling one of the standard widget manipula-
tion routines provided by the Intrinsics, or a widget class-
specific manipulation routine.

The Intrinsics provide generic routines to give the applica-
tion programmer access to a set of standard widget func-
tions.	The common widget routines let an application or
composite widget perform the following operations on widgets
without requiring explicit knowledge of the widget type.

o    Control the mapping of widget windows

o    Destroy a widget instance

o    Obtain an argument value

o    Set an argument value

2.8.1.	Mapping Widgets

By default, widget windows are mapped (made viewable) auto-
matically by XtRealizeWidget.  This behavior can be disabled
by using XtSetMappedWhenManaged, making the client responsi-
ble for calling XtMapWidget to make the widget viewable.



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Athena Widget Set			    X11, Release 6.4


void XtSetMappedWhenManaged(w, map_when_managed)
      Widget w;
      Boolean map_when_managed;


w	  Specifies the widget.

map_when_managed
	  Specifies the new value.  If map_when_managed is
	  True, the widget is mapped automatically when it
	  is realized.	If map_when_managed is False, the
	  client must call XtMapWidget or make a second call
	  to XtSetMappedWhenManaged to cause the child win-
	  dow to be mapped.


The definition for XtMapWidget is:

void XtMapWidget(w)
     Widget w;


w	  Specifies the widget.

When you are creating several children in sequence for a
previously realized common parent it is generally more effi-
cient to construct a list of children as they are created
(using XtCreateWidget) and then use XtManageChildren to
request that their parent managed them all at once.  By man-
aging a list of children at one time, the parent can avoid
wasteful duplication of geometry processing and the associ-
ated ``screen flash''.

void XtManageChildren(children, num_children)
      WidgetList children;
      Cardinal num_children;


children  Specifies a list of children to add.

num_children
	  Specifies the number of children to add.

If the parent is already visible on the screen, it is espe-
cially important to batch updates so that the minimum amount
of visible window reconfiguration is performed.

For further information about these functions, see the X
Toolkit Intrinsics -- C Language Interface.

2.8.2.	Destroying Widgets

To destroy a widget instance of any type, use
XtDestroyWidget.



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void XtDestroyWidget(w)
      Widget w;


w	  Specifies the widget.

XtDestroyWidget destroys the widget and recursively destroys
any children that it may have, including the windows created
by its children.  After calling XtDestroyWidget, no further
references should be made to the widget or any children that
the destroyed widget may have had.

2.8.3.	Retrieving Widget Resource Values

To retrieve the current value of a resource attribute asso-
ciated with a widget instance, use XtGetValues.

void XtGetValues(w, args, num_args)
      Widget w;
      ArgList args;
      Cardinal num_args;


w	  Specifies the widget.

args	  Specifies a variable-length argument list of name
	  and address pairs that contain the resource name
	  and the address into which the resource value is
	  stored.

num_args  Specifies the number of arguments in the argument
	  list.

The arguments and values passed in the argument list are
dependent on the widget. Note that the caller is responsible
for providing space into which the returned resource value
is copied; the ArgList contains a pointer to this storage
(e.g. x and y must be allocated as Position).  For further
information, see the X Toolkit Intrinsics -- C Language
Interface.

2.8.4.	Modifying Widget Resource Values

To modify the current value of a resource attribute associ-
ated with a widget instance, use XtSetValues.

void XtSetValues(w, args, num_args)
      Widget w;
      ArgList args;
      Cardinal num_args;


w	  Specifies the widget.




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args	  Specifies an array of name and value pairs that
	  contain the arguments to be modified and their new
	  values.

num_args  Specifies the number of arguments in the argument
	  list.

The arguments and values that are passed will depend on the
widget being modified.	Some widgets may not allow certain
resources to be modified after the widget instance has been
created or realized.  No notification is given if any part
of a XtSetValues request is ignored.

For further information about these functions, see the X
Toolkit Intrinsics -- C Language Interface.

			    Note

     The argument list entry for XtGetValues specifies
     the address to which the caller wants the value
     copied.  The argument list entry for XtSetValues,
     however, contains the new value itself, if the
     size of value is less than sizeof(XtArgVal)
     (architecture dependent, but at least
     sizeof(long)); otherwise, it is a pointer to the
     value.  String resources are always passed as
     pointers, regardless of the length of the string.


2.9.  Using the Client Callback Interface

Widgets can communicate changes in their state to their
clients by means of a callback facility.  The format for a
client's callback handler is:

void CallbackProc(w, client_data, call_data)
      Widget w;
      XtPointer client_data;
      XtPointer call_data;


w	  Specifies widget for which the callback is regis-
	  tered.

client_data
	  Specifies arbitrary client-supplied data that the
	  widget should pass back to the client when the
	  widget executes the client's callback procedure.
	  This is a way for the client registering the call-
	  back to also register client-specific data: a
	  pointer to additional information about the wid-
	  get, a reason for invoking the callback, and so
	  on. If no additional information is necessary,
	  NULL may be passed as this argument.	This field



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	  is also frequently known as the closure.

call_data Specifies any callback-specific data the widget
	  wants to pass to the client.	For example, when
	  Scrollbar executes its jumpProc callback list, it
	  passes the current position of the thumb in
	  call_data.

Callbacks can be registered either by creating an argument
containing the callback list described below or by using the
special convenience routines XtAddCallback and XtAddCall-
backs.	When the widget is created, a pointer to a list of
callback procedure and data pairs can be passed in the argu-
ment list to XtCreateWidget.  The list is of type
XtCallbackList:


typedef struct {
     XtCallbackProc callback;
     XtPointer closure;
} XtCallbackRec, *XtCallbackList;


The callback list must be allocated and initialized before
calling XtCreateWidget.  The end of the list is identified
by an entry containing NULL in callback and closure.  Once
the widget is created, the client can change or de-allocate
this list; the widget itself makes no further reference to
it.  The closure field contains the client_data passed to
the callback when the callback list is executed.

The second method for registering callbacks is to use XtAdd-
Callback after the widget has been created.

void XtAddCallback(w, callback_name, callback, client_data)
      Widget w;
      String callback_name;
      XtCallbackProc callback;
      XtPointer client_data;


w	  Specifies the widget to add the callback to.

callback_name
	  Specifies the callback list within the widget to
	  append to.

callback  Specifies the callback procedure to add.

client_data
	  Specifies the data to be passed to the callback
	  when it is invoked.





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XtAddCallback adds the specified callback to the list for
the named widget.

All widgets provide a callback list named destroyCallback
where clients can register procedures that are to be exe-
cuted when the widget is destroyed.  The destroy callbacks
are executed when the widget or an ancestor is destroyed.
The call_data argument is unused for destroy callbacks.

2.10.  Programming Considerations

This section provides some guidelines on how to set up an
application program that uses the X Toolkit.

2.10.1.  Writing Applications

When writing an application that uses the X Toolkit, you
should make sure that your application performs the follow-
ing:

1.   Include <X11/Intrinsic.h> in your application programs.
     This header file automatically includes <X11/Xlib.h>,
     so all Xlib functions also are defined.  It may also be
     necessary to include < X11/StringDefs.h > when setting
     up argument lists, as many of the XtNsomething defini-
     tions are only defined in this file.

2.   Include the widget-specific header files for each wid-
     get type that you need to use.  For example,
     <X11/Xaw/Label.h> and <X11/Xaw/Command.h>.

3.   Call the XtAppInitialize function before invoking any
     other toolkit or Xlib functions.  For further informa-
     tion, see Section 2.1 and the X Toolkit Intrinsics -- C
     Language Interface.

4.   To pass attributes to the widget creation routines that
     will override any site or user customizations, set up
     argument lists.  In this document, a list of valid
     argument names is provided in the discussion of each
     widget.  The names each have a global symbol defined
     that begins with XtN to help catch spelling errors.
     For example, XtNlabel is defined for the label resource
     of many widgets.

     For further information, see Section 2.9.2.2.

5.   When the argument list is set up, create the widget
     with the XtCreateManagedWidget function.  For further
     information, see Section 2.2 and the X Toolkit Intrin-
     sics -- C Language Interface.

6.   If the widget has any callback routines, set by the
     XtNcallback argument or the XtAddCallback function,



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     declare these routines within the application.

7.   After creating the initial widget hierarchy, windows
     must be created for each widget by calling XtReal-
     izeWidget on the top level widget.

8.   Most applications now sit in a loop processing events
     using XtAppMainLoop, for example:


     XtCreateManagedWidget(name, class, parent, args, num_args);
     XtRealizeWidget(shell);
     XtAppMainLoop(app_context);


     For information about this function, see the X Toolkit
     Intrinsics -- C Language Interface.

9.   Link your application with libXaw (the Athena widgets),
     libXmu (miscellaneous utilities), libXt (the X Toolkit
     Intrinsics), libSM (Session Management), libICE (Inter-
     Client Exchange), libXext (the extension library needed
     for the shape extension code which allows rounded Com-
     mand buttons), and libX11 (the core X library).  The
     following provides a sample command line:


     cc -o application application.c -lXaw -lXmu -lXt -lSM -lICE -lXext -lX11


2.10.2.  Changing Resource Values

The Intrinsics support two methods of changing the default
resource values; the resource manager, and an argument list
passed into XtCreateWidget.  While resources values will get
updated no matter which method you use, the two methods pro-
vide slightly different functionality.

Resource Manager
	       This method picks up resource definitions
	       described in Xlib -- C Language X Interface
	       from many different locations at run time.
	       The locations most important to the applica-
	       tion programmer are the fallback resources
	       and the app-defaults file, (see X Toolkit
	       Intrinsics -- C Language Interface for the
	       complete list).	Since these resource are
	       loaded at run time, they can be overridden by
	       the user, allowing an application to be cus-
	       tomized to fit the particular needs of each
	       individual user.  These values can also be
	       modified without the need to rebuild the
	       application, allowing rapid prototyping of
	       user interfaces.  Application programmers



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	       should use resources in preference to hard-
	       coded values whenever possible.

Argument Lists The values passed into the widget at creation
	       time via an argument list cannot be modified
	       by the user, and allow no opportunity for
	       customization.  It is used to set resources
	       that cannot be specified as strings (e.g.
	       callback lists) or resources that should not
	       be overridden (e.g. window depth) by the
	       user.

2.10.2.1.  Specifying Resources

It is important for all X Toolkit application programmers to
understand how to use the X Resource Manager to specify
resources for widgets in an X application.  This section
will describe the most common methods used to specify these
resources, and how to use the X Resource manager.

Xrdb	       The xrdb utility may be used to load a file
	       containing resources into the X server.
	       Once the resources are loaded, the resources
	       will affect any new applications started on
	       the display that they were loaded onto.

Application Defaults
	       The application defaults (app-defaults) file
	       (normally in /usr/lib/X11/app-defaults/class-
	       name) for an application is loaded whenever
	       the application is started.

The resource specification has two colon-separated parts, a
name, and a value.  The value is a string whose format is
dependent on the resource specified by name.  Name is con-
structed by appending a resource name to a full widget name.

The full widget name is a list of the name of every ancestor
of the desired widget separated by periods (.).  Each widget
also has a class associated with it.  A class is a type of
widget (e.g. Label or Scrollbar or Box).  Notice that class
names, by convention, begin with capital letters and
instance names begin with lower case letters.  The class of
any widget may be used in place of its name in a resource
specification.	Here are a few examples:

xman.form.button1
	       This is a fully specified resource name, and
	       will affect only widgets called button1 that
	       are children of widgets called form that are
	       children of applications named xman.  (Note
	       that while typically two widgets that are
	       siblings will have different names, it is not
	       prohibited.)



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Xman.Form.Command
	       This will match any Command widget that is a
	       child of a Form widget that is itself a child
	       of an application of class Xman.

Xman.Form.button1
	       This is a mixed resource name with both wid-
	       get names and classes specified.

This syntax allows an application programmer to specify any
widget in the widget tree.  To match more than one widget
(for example a user may want to make all Command buttons
blue), use an asterisk (*) instead of a period.  When an
asterisk is used, any number of widgets (including zero) may
exist between the two widget names. For example:

Xman*Command   This matches all Command widgets in the Xman
	       application.

Foo*button1    This matches any widget in the Foo applica-
	       tion that is named button1.

The root of all application widget trees is the widget
returned by XtAppInitialize.  Even though this is actually
an ApplicationShell widget, the toolkit replaces its widget
class with the class name of the application.  The name of
this widget is either the name used to invoke the applica-
tion (argv[0]) or the name of the application specified
using the standard -name command line option supported by
the Intrinsics.

The last step in constructing the resource name is to append
the name of the resource with either a period or asterisk to
the full or partial widget name already constructed.

*foreground:Blue      Specifies that all widgets in all
		      applications will have a foreground
		      color of blue.

Xman*borderWidth:10   Specifies that all widgets in an
		      application whose class is Xman will
		      have a border width of 10 (pixels).

xman.form.button1.label:Testing
		      Specifies that a particular widget in
		      the xman application will have a label
		      named Testing.

An exclamation point (!) in the first column of a line indi-
cates that the rest of the line should be treated as a com-
ment.

Final Words




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The Resource manager is a powerful tool that can be used
very effectively to customize X Toolkit applications at run
time by either the application programmer or the user.	Some
final points to note:

o    An application programmer may add new resources to
     their application.  These resources are associated with
     the global application, and not any particular widget.
     The X Toolkit function used for adding the application
     resources is XtGetApplicationResources.

o    Be careful when creating resource files.  Since widgets
     will ignore resources that they do not understand, any
     spelling errors will cause a resource to have no
     effect.

o    Only one resource line will match any given resource.
     There is a set of precedence rules, which take the fol-
     lowing general stance.

     o	  More specific overrides less specific, thus period
     always overrides asterisk.

     o	  Names on the left are more specific and override
     names on the right.

     o	  When resource specifications are exactly the same,
     user defaults
	  will override program defaults.

For a complete explanation of the rules of precedence, and
other specific topics see X Toolkit Intrinsics -- C Language
Interface and Xlib -- C Language X Interface.

2.10.2.2.  Creating Argument Lists

To set up an argument list for the inline specification of
widget attributes, you may use any of the four approaches
discussed in this section.  Each resource name has a global
symbol associated with it.  This global symbol has the form
XtNresource name.  For example, the symbol for ``fore-
ground'' is XtNforeground. For further information, see the
X Toolkit Intrinsics -- C Language Interface.

Argument are specified by using the following structure:


typedef struct {
     String name;
     XtArgVal value;
} Arg, *ArgList;






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The first approach is to statically initialize the argument
list.  For example:


static Arg arglist[] = {
     {XtNwidth, (XtArgVal) 400},
     {XtNheight, (XtArgVal) 300},
};


This approach is convenient for lists that do not need to be
computed at runtime and makes adding or deleting new ele-
ments easy.  The XtNumber macro is used to compute the num-
ber of elements in the argument list, preventing simple pro-
gramming errors:


     XtCreateWidget(name, class, parent, arglist, XtNumber(arglist));


The second approach is to use the XtSetArg macro.  For exam-
ple:


Arg arglist[10];
XtSetArg(arglist[1], XtNwidth, 400);
XtSetArg(arglist[2], XtNheight, 300);


To make it easier to insert and delete entries, you also can
use a variable index:


Arg arglist[10];
Cardinal i=0;
XtSetArg(arglist[i], XtNwidth,	400);	    i++;
XtSetArg(arglist[i], XtNheight, 300);	    i++;


The i variable can then be used as the argument list count
in the widget create function.	In this example, XtNumber
would return 10, not 2, and therefore is not useful.

			    Note

     You should not use auto-increment or auto-decre-
     ment within the first argument to XtSetArg.  As it
     is currently implemented, XtSetArg is a macro that
     dereferences the first argument twice.


The third approach is to individually set the elements of
the argument list array:




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Arg arglist[10];
arglist[0].name  = XtNwidth;
arglist[0].value = (XtArgVal) 400;
arglist[1].name  = XtNheight;
arglist[1].value = (XtArgVal) 300;


Note that in this example, as in the previous example,
XtNumber would return 10, not 2, and therefore would not be
useful.

The fourth approach is to use a mixture of the first and
third approaches: you can statically define the argument
list but modify some entries at runtime.  For example:


static Arg arglist[] = {
     {XtNwidth, (XtArgVal) 400},
     {XtNheight, (XtArgVal) NULL},
};
arglist[1].value = (XtArgVal) 300;


In this example, XtNumber can be used, as in the first
approach, for easier code maintenance.

2.11.  Example Programs

The best way to understand how to use any programming
library is by trying some simple examples.  A collection of
example programs that introduces each of the widgets in that
Athena widget set, as well as many important toolkit pro-
gramming concepts, is available in the X11R6 release as dis-
tributed by the X Consortium.  It can be found in the dis-
tribution directory contrib/examples/mit/Xaw, but see your
site administrator for the exact location of these files on
your system.  See the README file from that directory for a
guide to the examples.



















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			 Chapter 3

		       Simple Widgets




Each of these widgets performs a specific user interface
function.  They are simple because they cannot have widget
children--they may only be used as leaves of the widget
tree.  These widgets display information or take user input.


Command   A push button that, when selected, may cause a
	  specific action to take place.  This widget can
	  display a multi-line string or a bitmap or pixmap
	  image.

Grip	  A rectangle that, when selected, will cause an
	  action to take place.

Label	  A rectangle that can display a multi-line string
	  or a bitmap or pixmap image.

List	  A list of text strings presented in row column
	  format that may be individually selected.  When an
	  element is selected an action may take place.

Panner	  A rectangular area containing a slider that may be
	  moved in two dimensions.  Notification of movement
	  may be continuous or discrete.

Repeater  A push button that triggers an action at an
	  increasing rate when selected.  This widget can
	  display a multi-line string or a bitmap or pixmap
	  image.

Scrollbar A rectangular area containing a thumb that when
	  slid along one dimension may cause a specific
	  action to take place.  The Scrollbar may be ori-
	  ented horizontally or vertically.

Simple	  The base class for most of the simple widgets.
	  Provides a rectangular area with a settable mouse
	  cursor and special border.

StripChart
	  A real time data graph that will automatically
	  update and scroll.

Toggle	  A push button that contains state information.
	  Toggles may also be used as ``radio buttons'' to



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	  implement a ``one of many'' or ``zero or one of
	  many'' group of buttons.  This widget can display
	  a multi-line string or a bitmap or pixmap image.

3.1.  Command Widget


Application header file<X11/Xaw/Command.h>
Class header file   <X11/Xaw/CommandP.h>
Class		    commandWidgetClass
Class Name	    Command
Superclass	    Label



The Command widget is an area, often rectangular, that con-
tains text or a graphical image. Command widgets are often
referred to as ``push buttons.''  When the pointer is over a
Command widget, the widget becomes highlighted by drawing a
rectangle around its perimeter.  This highlighting indicates
that the widget is ready for selection.  When mouse button 1
is pressed, the Command widget indicates that it has been
selected by reversing its foreground and background colors.
When the mouse button is released, the Command widget's
notify action is invoked, calling all functions on its call-
back list.  If the pointer is moved off of the widget before
the pointer button is released, the widget reverts to its
normal foreground and background colors, and releasing the
pointer button has no effect.  This behavior allows the user
to cancel an action.

3.1.1.	Resources

When creating a Command widget instance, the following
resources are retrieved from the argument list or from the
resource database:


-------------------------------------------------------------------------------------------------
Name		      Class		Type		NotesDefault Value
-------------------------------------------------------------------------------------------------
accelerators	      Accelerators	AcceleratorTable     NULL
ancestorSensitive     AncestorSensitive Boolean 	D    True
background	      Background	Pixel		     XtDefaultBackground
backgroundPixmap      Pixmap		Pixmap		     XtUnspecifiedPixmap
bitmap		      Bitmap		Pixmap		     None
borderColor	      BorderColor	Pixel		     XtDefaultForeground
borderPixmap	      Pixmap		Pixmap		     XtUnspecifiedPixmap
borderWidth	      BorderWidth	Dimension	     1
callback	      Callback		XtCallbackList	     NULL
colormap	      Colormap		Colormap	     Parent's Colormap
cornerRoundPercent    CornerRoundPercentDimension	     25
cursor		      Cursor		Cursor		     None




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-------------------------------------------------------------------------------------------------
Name		      Class		Type		NotesDefault Value
-------------------------------------------------------------------------------------------------
cursorName	      Cursor		String		     NULL
depth		      Depth		int		C    Parent's Depth
destroyCallback       Callback		XtCallbackList	     NULL
encoding	      Encoding		UnsignedChar	     XawTextEncoding8bit
font		      Font		XFontStruct	     XtDefaultFont
foreground	      Foreground	Pixel		     XtDefaultForeground
height		      Height		Dimension	A    graphic height + 2 * internalHeight
highlightThickness    Thickness 	Dimension	A    2 (0 if Shaped)
insensitiveBorder     Insensitive	Pixmap		     GreyPixmap
internalHeight	      Height		Dimension	     2
internalWidth	      Width		Dimension	     4
international	      International	Boolean 	C    False
justify 	      Justify		Justify 	     XtJustifyCenter (center)
label		      Label		String		     name of widget
leftBitmap	      LeftBitmap	Bitmap		     None
mappedWhenManaged     MappedWhenManaged Boolean 	     True
pointerColor	      Foreground	Pixel		     XtDefaultForeground
pointerColorBackgroundBackground	Pixel		     XtDefaultBackground
resize		      Resize		Boolean 	     True
screen		      Screen		Screen		R    Parent's Screen
sensitive	      Sensitive 	Boolean 	     True
shapeStyle	      ShapeStyle	ShapeStyle	     Rectangle
translations	      Translations	TranslationTable     See below
width		      Width		Dimension	A    graphic width + 2 * internalWidth
x		      Position		Position	     0
y		      Position		Position	     0
-------------------------------------------------------------------------------------------------



accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap



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Athena Widget Set			    X11, Release 6.4


	       specified will be used instead of the back-
	       ground color.

bitmap	       A bitmap to display instead of the label.
	       The default size of the widget will be just
	       large enough to contain the bitmap and the
	       widget's internal width and height.  The
	       resource converter for this resource con-
	       structs bitmaps from the contents of files.
	       (See Converting Bitmaps for details.)  If
	       this bitmap is one bit deep then the 1's will
	       be rendered in the foreground color, and the
	       0's in the background color.  If bitmap has a
	       depth greater than one, it is copied directly
	       into the window.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

callback       A list of routines to be called when the
	       notify action is invoked.

colormap       The colormap that this widget will use.

cornerRoundPercent
	       When a ShapeStyle of roundedRectangle is
	       used, this resource controls the radius of
	       the rounded corner.  The radius of the
	       rounded corners is specified as a percentage
	       of the length of the shortest side of the
	       widget.

cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.

cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will over-
	       ride the cursor resource if both are speci-
	       fied. (See 2.4.1)

depth	       The depth of this widget's window.





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Athena Widget Set			    X11, Release 6.4


destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

encoding       The encoding method used by the value of the
	       label resource.	The value may be XawTextEn-
	       coding8bit or XawTextEncodingChar2b.  When
	       international is set to true this resource is
	       not used.

font	       The text font to use when displaying the
	       label, when the international resource is
	       false.

fontSet        The text font set to use when displaying the
	       label, when the international resource is
	       true.

foreground     A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       widget's window.  This color is also used to
	       render all 1's in a bitmap one plane deep.

height
width	       The height and width of this widget in pix-
	       els.

highlightThickness
	       The thickness of the rectangle that is used
	       to highlight the internal border of this wid-
	       get, alerting the user that it is ready to be
	       selected.  The default value is 2 pixels if
	       the shapeStyle is rectangle, and 0 Pixels (no
	       highlighting) otherwise.

insensitiveBorder
	       This pixmap will be tiled into the widget's
	       border if the widget becomes insensitive.

internalHeight
internalWidth  The minimum amount of space to leave between
	       the graphic and the vertical and horizontal
	       edges of the window.

international  This is a boolean flag, only settable at wid-
	       get creation time.  A value of false signals
	       the widget to use pre-R6 internationalization
	       (specifically, the lack thereof), such as
	       using fonts for displaying text, etc.  A
	       value of true directs the widget to act in an
	       internationalized manner, such as utilizing
	       font sets for displaying text, etc.





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justify        Specifies left, center, or right alignment of
	       graphic within the widget.  This resource may
	       be specified with the values XtJustifyLeft,
	       XtJustifyCenter, or XtJustifyRight.  A con-
	       verter is registered for this resource that
	       will convert the following strings: left,
	       right, and center.  This resource only has
	       noticeable effect when the width of the wid-
	       get is larger than necessary to display the
	       graphic.  Note that when the graphic is a
	       multi-line label, the longest line will obey
	       this justification while shorter lines will
	       be left-justified with the longest one.


label	       Specifies the text string to be displayed in
	       the widget's window if no bitmap is speci-
	       fied.  The default is the name of this wid-
	       get.  Irregardless of the value of encoding
	       or international, a single newline character
	       (1 byte) will cause a line break.

leftBitmap     Specifies a bitmap to display to the left of
	       the graphic in the widget's window.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.

pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

resize	       Specifies whether the widget should attempt
	       to resize to its preferred dimensions when-
	       ever its resources are modified with XtSet-
	       Values.	This attempt to resize may be denied
	       by the parent of this widget.  The parent is
	       always free to resize the widget regardless
	       of the state of this resource.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not



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	       get input events if either ancestorSensitive
	       or sensitive is False.

shapeStyle     Nonrectangular widgets may be created using
	       this resource.  Nonrectangular widgets are
	       supported only on a server that supports the
	       Shape Extension.  If nonrectangular widgets
	       are specified for a server lacking this
	       extension, the shape is ignored and the wid-
	       gets will be rectangular.  The following
	       shapes are currently supported: XmuShapeRect-
	       angle, XmuShapeOval, XmuShapeEllipse, and
	       XmuShapeRoundedRectangle.  A converter is
	       registered for this resource that will con-
	       vert the following strings: rectangle, oval,
	       ellipse, and roundedRectangle.

translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

3.1.2.	Command Actions

The Command widget supports the following actions:

o    Switching the button's interior between the foreground
     and background colors with set, unset, and reset.

o    Processing application callbacks with notify

o    Switching the internal border between highlighted and
     unhighlighted states with highlight and unhighlight

The following are the default translation bindings used by
the Command widget:


     <EnterWindow>:   highlight()
     <LeaveWindow>:   reset()
     <Btn1Down>:      set()
     <Btn1Up>:	      notify() unset()


The full list of actions supported by Command is:

highlight(condition)
	       Displays the internal highlight border in the
	       color (foreground or background ) that con-
	       trasts with the interior color of the Command
	       widget.	The conditions WhenUnset and Always
	       are understood by this action procedure.  If



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Athena Widget Set			    X11, Release 6.4


	       no argument is passed, WhenUnset is assumed.

unhighlight()  Displays the internal highlight border in the
	       color (foreground or background ) that
	       matches the interior color of the Command
	       widget.

set()	       Enters the set state, in which notify is pos-
	       sible.  This action causes the button to dis-
	       play its interior in the foreground color.
	       The label or bitmap is displayed in the back-
	       ground color.

unset()        Cancels the set state and displays the inte-
	       rior of the button in the background color.
	       The label or bitmap is displayed in the fore-
	       ground color.

reset()        Cancels any set or highlight and displays the
	       interior of the button in the background
	       color, with the label or bitmap displayed in
	       the foreground color.

notify()       When the button is in the set state this
	       action calls all functions in the callback
	       list named by the callback resource.  The
	       value of the call_data argument passed to
	       these functions is undefined.

A very common alternative to registering callbacks is to
augment a Command's translations with an action performing
the desired function.  This often takes the form of:


*Myapp*save.translations: #augment <Btn1Down>,<Btn1Up>: Save()



			    Note

     When a bitmap of depth greater that one (1) is
     specified the set(), unset(), and reset() actions
     have no effect, since there are no foreground and
     background colors used in a multi-plane pixmap.


3.2.  Grip Widget


Application header file<X11/Xaw/Grip.h>
Class header file   <X11/Xaw/GripP.h>
Class		    gripWidgetClass
Class Name	    Grip
Superclass	    Simple



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The Grip widget provides a small rectangular region in which
user input events (such as ButtonPress or ButtonRelease) may
be handled.  The most common use for the Grip widget is as
an attachment point for visually repositioning an object,
such as the pane border in a Paned widget.

3.2.1.	Resources

When creating a Grip widget instance, the following
resources are retrieved from the argument list or from the
resource database:


---------------------------------------------------------------------------------
Name		      Class	       Type	       NotesDefault Value
---------------------------------------------------------------------------------
accelerators	      Accelerators     AcceleratorTable     NULL
ancestorSensitive     AncestorSensitiveBoolean	       D    True
background	      Background       Pixel		    XtDefaultBackground
backgroundPixmap      Pixmap	       Pixmap		    XtUnspecifiedPixmap
borderColor	      BorderColor      Pixel		    XtDefaultForeground
borderPixmap	      Pixmap	       Pixmap		    XtUnspecifiedPixmap
borderWidth	      BorderWidth      Dimension	    0
callback	      Callback	       Callback 	    NULL
colormap	      Colormap	       Colormap 	    Parent's Colormap
cursor		      Cursor	       Cursor		    None
cursorName	      Cursor	       String		    NULL
depth		      Depth	       int	       C    Parent's Depth
destroyCallback       Callback	       XtCallbackList	    NULL
foreground	      Foreground       Pixel		    XtDefaultForeground
height		      Height	       Dimension	    8
insensitiveBorder     Insensitive      Pixmap		    GreyPixmap
international	      International    Boolean	       C    False
mappedWhenManaged     MappedWhenManagedBoolean		    True
pointerColor	      Foreground       Pixel		    XtDefaultForeground
pointerColorBackgroundBackground       Pixel		    XtDefaultBackground
screen		      Screen	       Screen	       R    Parent's Screen
sensitive	      Sensitive        Boolean		    True
translations	      Translations     TranslationTable     NULL
width		      Width	       Dimension	    8
x		      Position	       Position 	    0
y		      Position	       Position 	    0
---------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if



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Athena Widget Set			    X11, Release 6.4


	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

callback       All routines on this list are called whenever
	       the GripAction action routine is invoked.
	       The call_data contains all information passed
	       to the action routine.  A detailed descrip-
	       tion is given below in the Grip Actions sec-
	       tion.

colormap       The colormap that this widget will use.

cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.

cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will over-
	       ride the cursor resource if both are speci-
	       fied. (See 2.4.1)

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

foreground     A pixel value which indexes the widget's col-
	       ormap to derive the color used to flood fill



			     36





Athena Widget Set			    X11, Release 6.4


	       the entire Grip widget.

height
width	       The height and width of this widget in pix-
	       els.

insensitiveBorder
	       This pixmap will be tiled into the widget's
	       border if the widget becomes insensitive.

international  This is a boolean flag, only settable at wid-
	       get creation time.  While not utilized in
	       this widget, it can and should be checked by
	       any subclasses that have behavior that should
	       vary with locale.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.

pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

3.2.2.	Grip Actions

The Grip widget does not declare any default event transla-
tion bindings, but it does declare a single action routine
named GripAction.  The client specifies an arbitrary event
translation table, optionally giving parameters to the Gri-
pAction routine.



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Athena Widget Set			    X11, Release 6.4


The GripAction routine executes the callbacks on the call-
back list, passing as call_data a pointer to a XawGripCall-
Data structure, defined in the Grip widget's application
header file.



typedef struct _XawGripCallData {
     XEvent *event;
     String *params;
     Cardinal num_params;
} XawGripCallDataRec, *XawGripCallData,
  GripCallDataRec, *GripCallData; /* supported for R4 compatibility */



In this structure, the event is a pointer to the input event
that triggered the action.  params and num_params give the
string parameters specified in the translation table for the
particular event binding.

The following is an example of a translation table that uses
the GripAction:



     <Btn1Down>:	 GripAction(press)
     <Btn1Motion>:	 GripAction(move)
     <Btn1Up>:		 GripAction(release)


For a complete description of the format of translation
tables, see the X Toolkit Intrinsics -- C Language Inter-
face.

3.3.  Label Widget


Application header file<X11/Xaw/Label.h>
Class header file   <X11/Xaw/LabelP.h>
Class		    labelWidgetClass
Class Name	    Label
Superclass	    Simple



A Label widget holds a graphic displayed within a rectangu-
lar region of the screen.  The graphic may be a text string
containing multiple lines of characters in an 8 bit or 16
bit character set (to be displayed with a font), or in a
multi-byte encoding (for use with a fontset).  The graphic
may also be a bitmap or pixmap.  The Label widget will allow
its graphic to be left, right, or center justified.  Nor-
mally, this widget can be neither selected nor directly



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Athena Widget Set			    X11, Release 6.4


edited by the user.  It is intended for use as an output
device only.

3.3.1.	Resources

When creating a Label widget instance, the following
resources are retrieved from the argument list or from the
resource database:


------------------------------------------------------------------------------------------------
Name		      Class	       Type	       NotesDefault Value
------------------------------------------------------------------------------------------------
accelerators	      Accelerators     AcceleratorTable     NULL
ancestorSensitive     AncestorSensitiveBoolean	       D    True
background	      Background       Pixel		    XtDefaultBackground
backgroundPixmap      Pixmap	       Pixmap		    XtUnspecifiedPixmap
bitmap		      Bitmap	       Pixmap		    None
borderColor	      BorderColor      Pixel		    XtDefaultForeground
borderPixmap	      Pixmap	       Pixmap		    XtUnspecifiedPixmap
borderWidth	      BorderWidth      Dimension	    1
colormap	      Colormap	       Colormap 	    Parent's Colormap
cursor		      Cursor	       Cursor		    None
cursorName	      Cursor	       String		    NULL
depth		      Depth	       int	       C    Parent's Depth
destroyCallback       Callback	       XtCallbackList	    NULL
encoding	      Encoding	       UnsignedChar	    XawTextEncoding8bit
font		      Font	       XFontStruct	    XtDefaultFont
fontSet 	      FontSet	       XFontSet 	    XtDefaultFontSet
foreground	      Foreground       Pixel		    XtDefaultForeground
height		      Height	       Dimension       A    graphic height + 2 * internalHeight
insensitiveBorder     Insensitive      Pixmap		    GreyPixmap
internalHeight	      Height	       Dimension	    2
internalWidth	      Width	       Dimension	    4
international	      International    Boolean	       C    False
justify 	      Justify	       Justify		    XtJustifyCenter (center)
label		      Label	       String		    name of widget
leftBitmap	      LeftBitmap       Bitmap		    None
mappedWhenManaged     MappedWhenManagedBoolean		    True
pointerColor	      Foreground       Pixel		    XtDefaultForeground
pointerColorBackgroundBackground       Pixel		    XtDefaultBackground
resize		      Resize	       Boolean		    True
screen		      Screen	       Screen	       R    Parent's Screen
sensitive	      Sensitive        Boolean		    True
translations	      Translations     TranslationTable     See above
width		      Width	       Dimension       A    graphic width + 2 * internalWidth
x		      Position	       Position 	    0
y		      Position	       Position 	    0
------------------------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X



			     39





Athena Widget Set			    X11, Release 6.4


	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

bitmap	       A bitmap to display instead of the label.
	       The default size of the widget will be just
	       large enough to contain the bitmap and the
	       widget's internal width and height.  The
	       resource converter for this resource con-
	       structs bitmaps from the contents of files.
	       (See Converting Bitmaps for details.)  If
	       this bitmap is one bit deep then the 1's will
	       be rendered in the foreground color, and the
	       0's in the background color.  If bitmap has a
	       depth greater than one, it is copied directly
	       into the window.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

colormap       The colormap that this widget will use.

cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.





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Athena Widget Set			    X11, Release 6.4


cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will over-
	       ride the cursor resource if both are speci-
	       fied. (See 2.4.1)

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

encoding       The encoding method used by the value of the
	       label resource.	The value may be XawTextEn-
	       coding8bit or XawTextEncodingChar2b.  When
	       international is set to true this resource is
	       not used.

font	       The text font to use when displaying the
	       label, when the international resource is
	       false.

fontSet        The text font set to use when displaying the
	       label, when the international resource is
	       true.

foreground     A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       widget's window.  This color is also used to
	       render all 1's in a bitmap one plane deep.

height
width	       The height and width of this widget in pix-
	       els.

insensitiveBorder
	       This pixmap will be tiled into the widget's
	       border if the widget becomes insensitive.

internalHeight
internalWidth  The minimum amount of space to leave between
	       the graphic and the vertical and horizontal
	       edges of the window.

international  This is a boolean flag, only settable at wid-
	       get creation time.  A value of false signals
	       the widget to use pre-R6 internationalization
	       (specifically, the lack thereof), such as
	       using fonts for displaying text, etc.  A
	       value of true directs the widget to act in an
	       internationalized manner, such as utilizing
	       font sets for displaying text, etc.

justify        Specifies left, center, or right alignment of
	       graphic within the widget.  This resource may



			     41





Athena Widget Set			    X11, Release 6.4


	       be specified with the values XtJustifyLeft,
	       XtJustifyCenter, or XtJustifyRight.  A con-
	       verter is registered for this resource that
	       will convert the following strings: left,
	       right, and center.  This resource only has
	       noticeable effect when the width of the wid-
	       get is larger than necessary to display the
	       graphic.  Note that when the graphic is a
	       multi-line label, the longest line will obey
	       this justification while shorter lines will
	       be left-justified with the longest one.


label	       Specifies the text string to be displayed in
	       the widget's window if no bitmap is speci-
	       fied.  The default is the name of this wid-
	       get.  Irregardless of the value of encoding
	       or international, a single newline character
	       (1 byte) will cause a line break.

leftBitmap     Specifies a bitmap to display to the left of
	       the graphic in the widget's window.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.

pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

resize	       Specifies whether the widget should attempt
	       to resize to its preferred dimensions when-
	       ever its resources are modified with XtSet-
	       Values.	This attempt to resize may be denied
	       by the parent of this widget.  The parent is
	       always free to resize the widget regardless
	       of the state of this resource.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.



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Athena Widget Set			    X11, Release 6.4


translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

3.4.  List Widget



Application header file<X11/Xaw/List.h>
Class header file   <X11/Xaw/ListP.h>
Class		    listWidgetClass
Class Name	    List
Superclass	    Simple




The List widget contains a list of strings formatted into
rows and columns. When one of the strings is selected, it is
highlighted, and the List widget's Notify action is invoked,
calling all routines on its callback list.  Only one string
may be selected at a time.

3.4.1.	Resources

When creating a List widget instance, the following
resources are retrieved from the argument list or from the
resource database:


----------------------------------------------------------------------------------------------
Name		      Class	       Type	       NotesDefault Value
----------------------------------------------------------------------------------------------
accelerators	      Accelerators     AcceleratorTable     NULL
ancestorSensitive     AncestorSensitiveBoolean	       D    True
background	      Background       Pixel		    XtDefaultBackground
backgroundPixmap      Pixmap	       Pixmap		    XtUnspecifiedPixmap
borderColor	      BorderColor      Pixel		    XtDefaultForeground
borderPixmap	      Pixmap	       Pixmap		    XtUnspecifiedPixmap
borderWidth	      BorderWidth      Dimension	    1
callback	      Callback	       Callback 	    NULL
colormap	      Colormap	       Colormap 	    Parent's Colormap
columnSpacing	      Spacing	       Dimension	    6
cursor		      Cursor	       Cursor		    XC_left_ptr
cursorName	      Cursor	       String		    NULL
defaultColumns	      Columns	       int		    2
depth		      Depth	       int	       C    Parent's Depth
destroyCallback       Callback	       XtCallbackList	    NULL
font		      Font	       FontStruct	    XtDefaultFont
fontSet 	      FontSet	       XFontSet 	    XtDefaultFontSet




			     43





Athena Widget Set			    X11, Release 6.4


----------------------------------------------------------------------------------------------
Name		      Class	       Type	       NotesDefault Value
----------------------------------------------------------------------------------------------
forceColumns	      Columns	       Boolean		    False
foreground	      Foreground       Pixel		    XtDefaultForeground
height		      Height	       Dimension       A    Enough space to contain the list
insensitiveBorder     Insensitive      Pixmap		    GreyPixmap
internalHeight	      Height	       Dimension	    2
internalWidth	      Width	       Dimension	    4
international	      International    Boolean	       C    False
list		      List	       Pointer		    name of widget
longest 	      Longest	       int	       A    0
mappedWhenManaged     MappedWhenManagedBoolean		    True
numberStrings	      NumberStrings    int	       A    computed for NULL terminated list
pasteBuffer	      Boolean	       Boolean		    False
pointerColor	      Foreground       Pixel		    XtDefaultForeground
pointerColorBackgroundBackground       Pixel		    XtDefaultBackground
rowSpacing	      Spacing	       Dimension	    2
screen		      Screen	       Screen	       R    Parent's Screen
sensitive	      Sensitive        Boolean		    True
translations	      Translations     TranslationTable     See below
verticalList	      Boolean	       Boolean		    False
width		      Width	       Dimension       A    Enough space to contain the list
x		      Position	       Position 	    0
y		      Position	       Position 	    0
----------------------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the



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	       widget's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

callback       All functions on this list are called when-
	       ever the notify action is invoked.  The
	       call_data argument contains information about
	       the element selected and is described in
	       detail in the List Callbacks section.

colormap       The colormap that this widget will use.

columnSpacing
rowSpacing     The amount of space, in pixels, between each
	       of the rows and columns in the list.

cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.

cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will over-
	       ride the cursor resource if both are speci-
	       fied. (See 2.4.1)

defaultColumns The default number of columns.  This value is
	       used when neither the width nor the height of
	       the List widget is specified or when
	       forceColumns is True.

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

font	       The text font to use when displaying the
	       list, when the international resource is
	       false.

fontSet        The text font set to use when displaying the
	       list, when the international resource is
	       true.

forceColumns   Forces the default number of columns to be
	       used regardless of the List widget's current
	       size.



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foreground     A pixel value which indexes the widget's col-
	       ormap to derive the color used to paint the
	       text of the list elements.

height
width	       The height and width of this widget in pix-
	       els.

insensitiveBorder
	       This pixmap will be tiled into the widget's
	       border if the widget becomes insensitive.

internalHeight
internalWidth  The margin, in pixels, between the edges of
	       the list and the corresponding edge of the
	       List widget's window.

list	       An array of text strings displayed in the
	       List widget.  If numberStrings is zero (the
	       default) then the list must be NULL termi-
	       nated.  If a value is not specified for the
	       list, then numberStrings is set to 1, and the
	       name of the widget is used as the list, and
	       longest is set to the length of the name of
	       the widget.  The list is used in place, and
	       must be available to the List widget for the
	       lifetime of this widget, or until it is
	       changed with XtSetValues or XawListChange.

international  This is a boolean flag, only settable at wid-
	       get creation time.  A value of false signals
	       the widget to use pre-R6 internationalization
	       (specifically, the lack thereof), such as
	       using fonts for displaying text, etc.  A
	       value of true directs the widget to act in an
	       internationalized manner, such as utilizing
	       font sets for displaying text, etc.

longest        Specifies the width, in pixels, of the
	       longest string in the current list.  The List
	       widget will compute this value if zero (the
	       default) is specified.  If this resource is
	       set by hand, entries longer than this will be
	       clipped to fit.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

numberStrings  The number of strings in the current list.
	       If a value of zero (the default) is speci-
	       fied, the List widget will compute it.  When
	       computing the number of strings the List



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	       widget assumes that the list is NULL termi-
	       nated.

pasteBuffer    If this resource is set to True then the name
	       of the currently selected list element will
	       be put into CUT_BUFFER_0.

pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.

pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

translations   The event bindings associated with this wid-
	       get.

verticalList   If this resource is set to True then the list
	       elements will be presented in column major
	       order.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

3.4.2.	List Actions

The List widget supports the following actions:

o    Highlighting and unhighlighting the list element under
     the pointer with Set and Unset

o    Processing application callbacks with Notify

The following is the default translation table used by the
List Widget:


     <Btn1Down>,<Btn1Up>:  Set() Notify()






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The full list of actions supported by List widget is:

Set()	       Sets the list element that is currently under
	       the pointer.  To inform the user that this
	       element is currently set, it is drawn with
	       foreground and background colors reversed.
	       If this action is called when there is no
	       list element under the cursor, the currently
	       set element will be unset.

Unset()        Cancels the set state of the element under
	       the pointer, and redraws it with normal fore-
	       ground and background colors.

Notify()       Calls all callbacks on the List widget's
	       callback list.  Information about the cur-
	       rently selected list element is passed in the
	       call_data argument (see List Callbacks
	       below).

3.4.3.	List Callbacks

All procedures on the List widget's callback list will have
a XawListReturnStruct passed to them as call_data.  The
structure is defined in the List widget's application header
file.


typedef struct _XawListReturnStruct {
     String string;   /* string shown in the list. */
     int list_index;  /* index of the item selected. */
} XawListReturnStruct;

			    Note

     The list_index item used to be called simply
     index.  Unfortunately, this name collided with a
     global name defined on some operating systems, and
     had to be changed.



3.4.4.	Changing the List

To change the list that is displayed, use XawListChange.

void XawListChange(w, list, nitems, longest, resize)
     Widget w;
     String * list;
     int nitems, longest;
     Boolean resize;






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w	  Specifies the List widget.

list	  Specifies the new list for the List widget to dis-
	  play.

nitems	  Specifies the number of items in the list.  If a
	  value less than 1 is specified, list must be NULL
	  terminated, and the number of items will be calcu-
	  lated by the List widget.

longest   Specifies the length of the longest item in the
	  list in pixels.  If a value less than 1 is speci-
	  fied, the List widget will calculate the value.

resize	  Specifies a Boolean value that if True indicates
	  that the List widget should try to resize itself
	  after making the change.  The constraints of the
	  List widget's parent are always enforced, regard-
	  less of the value specified here.

XawListChange will unset all list elements that are cur-
rently set before the list is actually changed.  The list is
used in place, and must remain usable for the lifetime of
the List widget, or until list has been changed again with
this function or with XtSetValues.

3.4.5.	Highlighting an Item

To highlight an item in the list, use XawListHighlight.

void XawListHighlight(w, item)
     Widget w;
     int item;


w	  Specifies the List widget.

item	  Specifies an index into the current list that
	  indicates the item to be highlighted.

Only one item can be highlighted at a time.  If an item is
already highlighted when XawListHighlight is called, the
highlighted item is unhighlighted before the new item is
highlighted.

3.4.6.	Unhighlighting an Item

To unhighlight the currently highlighted item in the list,
use XawListUnhighlight.

void XawListUnhighlight(w)
     Widget w;





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w	  Specifies the List widget.

3.4.7.	Retrieving the Currently Selected Item

To retrieve the list element that is currently set, use
XawListShowCurrent.

XawListReturnStruct *XawListShowCurrent(w)
     Widget w;


w	  Specifies the List widget.

XawListShowCurrent returns a pointer to an XawListReturn-
Struct structure, containing the currently highlighted item.
If the value of the index member is XAW_LIST_NONE, the
string member is undefined, and no item is currently
selected.

3.4.8.	Restrictions

Many programmers create a ``scrolled list'' by putting a
List widget with many entries as a child of a Viewport wid-
get.  The List continues to create a window as big as its
contents, but that big window is only visible where it
intersects the parent Viewport's window.  (I.e., it is
``clipped.'')

While this is a useful technique, there is a serious draw-
back.  X does not support windows above 32,767 pixels in
width or height, but this height limit will be exceeded by a
List's window when the List has many entries (i.e., with a
12 point font, about 3000 entries would be too many.)


3.5.  Panner Widget



Application header file<X11/Xaw/Panner.h>
Class header file   <X11/Xaw/PannerP.h>
Class		    pannerWidgetClass
Class Name	    Panner
Superclass	    Simple



A Panner widget is a rectangle, called the ``canvas,'' on
which another rectangle, the ``slider,'' moves in two dimen-
sions.	It is often used with a Porthole widget to move, or
``scroll,'' a third widget in two dimensions, in which case
the slider's size and position gives feedback as to what
portion of the third widget is visible.




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The slider may be scrolled around the canvas by pressing,
dragging, and releasing Button1; the default translation
also enables scrolling via arrow keys and some other keys.
While scrolling is in progress, the application receives
notification through callback procedures.  Notification may
be done either continuously whenever the slider moves or
discretely whenever the slider has been given a new loca-
tion.

3.5.1.	Resources

When creating a Panner widget instance, the following
resources are retrieved from the argument list or from the
resource database:


-----------------------------------------------------------------------------------
Name		      Class	       Type	       NotesDefault Value
-----------------------------------------------------------------------------------
accelerators	      Accelerators     AcceleratorTable     NULL
allowOff	      AllowOff	       Boolean		    False
ancestorSensitive     AncestorSensitiveBoolean	       D    True
background	      Background       Pixel		    XtDefaultBackground
backgroundPixmap      Pixmap	       Pixmap		    XtUnspecifiedPixmap
backgroundStipple     BackgroundStippleString		    NULL
borderColor	      BorderColor      Pixel		    XtDefaultForeground
borderPixmap	      Pixmap	       Pixmap		    XtUnspecifiedPixmap
borderWidth	      BorderWidth      Dimension	    1
canvasHeight	      CanvasHeight     Dimension	    0
canvasWidth	      CanvasWidth      Dimension	    0
colormap	      Colormap	       Colormap 	    Parent's Colormap
cursor		      Cursor	       Cursor		    None
cursorName	      Cursor	       String		    NULL
defaultScale	      DefaultScale     Dimension	    8
depth		      Depth	       int	       C    Parent's Depth
destroyCallback       Callback	       XtCallbackList	    NULL
foreground	      Foreground       Pixel		    XtDefaultForeground
height		      Height	       Dimension       A    depends on orientation
internalSpace	      InternalSpace    Dimension	    4
international	      International    Boolean	       C    False
lineWidth	      LineWidth        Dimension	    0
mappedWhenManaged     MappedWhenManagedBoolean		    True
pointerColor	      Foreground       Pixel		    XtDefaultForeground
pointerColorBackgroundBackground       Pixel		    XtDefaultBackground
reportCallback	      ReportCallback   Callback 	    NULL
resize		      Resize	       Boolean		    True
rubberBand	      RubberBand       Boolean		    False
screen		      Screen	       Screen	       R    Parent's Screen
sensitive	      Sensitive        Boolean		    True
shadowColor	      ShadowColor      Pixel		    XtDefaultForeground
shadowThickness       ShadowThickness  Dimension	    2
sliderX 	      SliderX	       Position 	    0
sliderY 	      SliderY	       Position 	    0




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-----------------------------------------------------------------------------------
Name		      Class	       Type	       NotesDefault Value
-----------------------------------------------------------------------------------
sliderHeight	      SliderHeight     Dimension	    0
sliderWidth	      SliderWidth      Dimension	    0
translations	      Translations     TranslationTable     See below
width		      Width	       Dimension       A    depends on orientation
x		      Position	       Position 	    0
y		      Position	       Position 	    0
-----------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

allowOff       Whether to allow the edges of the slider to
	       go off the edges of the canvas.

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

backgroundStipple
	       The name of a bitmap pattern to be used as
	       the background for the area representing the
	       canvas.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.




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borderWidth    The width of this widget's window border.

canvasHeight
canvasWidth    The size of the canvas.

colormap       The colormap that this widget will use.

cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.

cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will over-
	       ride the cursor resource if both are speci-
	       fied. (See 2.4.1)

defaultScale   The percentage size that the Panner widget
	       should have relative to the size of the can-
	       vas.

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

foreground     A pixel value which indexes the widget's col-
	       ormap to derive the color used to draw the
	       slider.

height
width	       The height and width of this widget in pix-
	       els.

internalSpace  The width of internal border in pixels
	       between a slider representing the full size
	       of the canvas and the edge of the Panner wid-
	       get.

international  This is a boolean flag, only settable at wid-
	       get creation time.  While not utilized in
	       this widget, it can and should be checked by
	       any subclasses that have behavior that should
	       vary with locale.

lineWidth      The width of the lines in the rubberbanding
	       rectangle when rubberbanding is in effect
	       instead of continuous scrolling.  The default
	       is 0.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the



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	       Toolkit when it is realized and managed.

pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.

pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

reportCallback All functions on this callback list are
	       called when the notify action is invoked.
	       See the Panner Actions section for details.

resize	       Whether or not to resize the panner whenever
	       the canvas size is changed so that the
	       defaultScale is maintained.

rubberBand     Whether or not scrolling should be discrete
	       (only moving a rubberbanded rectangle until
	       the scrolling is done) or continuous (moving
	       the slider itself).  This controls whether or
	       not the move action procedure also invokes
	       the notify action procedure.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

shadowColor    The color of the shadow underneath the
	       slider.

shadowThickness
	       The width of the shadow underneath the
	       slider.

sliderX
sliderY        The location of the slider in the coordinates
	       of the canvas.

sliderHeight
sliderWidth    The size of the slider.

translations   The event bindings associated with this wid-
	       get.





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x
y	       The location of the upper left outside corner
	       of this widget in its parent.

3.5.2.	Panner Actions

The actions supported by the Panner widget are:

start()        This action begins movement of the slider.

stop()	       This action ends movement of the slider.

abort()        This action ends movement of the slider and
	       restores it to the position it held when the
	       start action was invoked.

move()	       This action moves the outline of the slider
	       (if the rubberBand resource is True) or the
	       slider itself (by invoking the notify action
	       procedure).

page(xamount,yamount)
	       This action moves the slider by the specified
	       amounts.  The format for the amounts is a
	       signed or unsigned floating-point number
	       (e.g., +1.0 or -.5) followed by either p
	       indicating pages (slider sizes), or c indi-
	       cating canvas sizes.  Thus, page(+0,+.5p)
	       represents vertical movement down one-half
	       the height of the slider and page(0,0) repre-
	       sents moving to the upper left corner of the
	       canvas.

notify()       This action informs the application of the
	       slider's current position by invoking the
	       reportCallback functions registered by the
	       application.

set(what,value)
	       This action changes the behavior of the Pan-
	       ner.  The what argument must currently be the
	       string rubberband and controls the value of
	       the rubberBand resource.  The value argument
	       may have one of the values on, off, or tog-
	       gle.


The default bindings for Panner are:


     <Btn1Down>: start()
     <Btn1Motion>:move()
     <Btn1Up>:	 notify() stop()
     <Btn2Down>: abort()



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     <Key>KP_Enter:set(rubberband,toggle)
     <Key>space: page(+1p,+1p)
     <Key>Delete:page(-1p,-1p)
     <Key>BackSpace:page(-1p,-1p)
     <Key>Left:  page(-.5p,+0)
     <Key>Right: page(+.5p,+0)
     <Key>Up:	 page(+0,-.5p)
     <Key>Down:  page(+0,+.5p)
     <Key>Home:  page(0,0)


3.5.3.	Panner Callbacks

The functions registered on the reportCallback list are
invoked by the notify action as follows:

void ReportProc(panner, client_data, report)
     Widget panner;
     XtPointer client_data;
     XtPointer report;	  /* (XawPannerReport *) */


panner	  Specifies the Panner widget.

client_data
	  Specifies the client data.

report	  Specifies a pointer to an XawPannerReport struc-
	  ture containing the location and size of the
	  slider and the size of the canvas.

3.6.  Repeater Widget


Application header file<X11/Xaw/Repeater.h>
Class header file   <X11/Xaw/RepeaterP.h>
Class		    repeaterWidgetClass
Class Name	    Repeater
Superclass	    Command



The Repeater widget is a subclass of the Command widget; see
the Command documentation for details.	The difference is
that the Repeater can call its registered callbacks repeat-
edly, at an increasing rate.  The default translation does
so for the duration the user holds down pointer button 1
while the pointer is on the Repeater.

3.6.1.	Resources

When creating a Repeater widget instance, the following
resources are retrieved from the argument list or from the
resource database:



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Athena Widget Set			    X11, Release 6.4


-------------------------------------------------------------------------------------------------
Name		      Class		Type		NotesDefault Value
-------------------------------------------------------------------------------------------------
accelerators	      Accelerators	AcceleratorTable     NULL
ancestorSensitive     AncestorSensitive Boolean 	D    True
background	      Background	Pixel		     XtDefaultBackground
backgroundPixmap      Pixmap		Pixmap		     XtUnspecifiedPixmap
bitmap		      Bitmap		Pixmap		     None
borderColor	      BorderColor	Pixel		     XtDefaultForeground
borderPixmap	      Pixmap		Pixmap		     XtUnspecifiedPixmap
borderWidth	      BorderWidth	Dimension	     1
callback	      Callback		XtCallbackList	     NULL
colormap	      Colormap		Colormap	     Parent's Colormap
cornerRoundPercent    CornerRoundPercentDimension	     25
cursor		      Cursor		Cursor		     None
cursorName	      Cursor		String		     NULL
decay		      Decay		Int		     5
depth		      Depth		int		C    Parent's Depth
destroyCallback       Callback		XtCallbackList	     NULL
encoding	      Encoding		UnsignedChar	     XawTextEncoding8bit
flash		      Boolean		Boolean 	     False
font		      Font		XFontStruct	     XtDefaultFont
fontSet 	      FontSet		XFontSet	     XtDefaultFontSet
foreground	      Foreground	Pixel		     XtDefaultForeground
height		      Height		Dimension	A    graphic height + 2 * internalHeight
highlightThickness    Thickness 	Dimension	A    2 (0 if Shaped)
initialDelay	      Delay		Int		     200
insensitiveBorder     Insensitive	Pixmap		     GreyPixmap
internalHeight	      Height		Dimension	     2
internalWidth	      Width		Dimension	     4
international	      International	Boolean 	C    False
justify 	      Justify		Justify 	     XtJustifyCenter (center)
label		      Label		String		     name of widget
leftBitmap	      LeftBitmap	Bitmap		     None
mappedWhenManaged     MappedWhenManaged Boolean 	     True
minimumDelay	      MinimumDelay	Int		     10
pointerColor	      Foreground	Pixel		     XtDefaultForeground
pointerColorBackgroundBackground	Pixel		     XtDefaultBackground
repeatDelay	      Delay		Int		     50
resize		      Resize		Boolean 	     True
screen		      Screen		Pointer 	R    Parent's Screen
sensitive	      Sensitive 	Boolean 	     True
shapeStyle	      ShapeStyle	ShapeStyle	     Rectangle
startCallback	      StartCallback	Callback	     NULL
stopCallback	      StopCallback	Callback	     NULL
translations	      Translations	TranslationTable     See below
width		      Width		Dimension	A    graphic width + 2 * internalWidth
x		      Position		Position	     0
y		      Position		Position	     0
-------------------------------------------------------------------------------------------------







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accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

bitmap	       A bitmap to display instead of the label.
	       The default size of the widget will be just
	       large enough to contain the bitmap and the
	       widget's internal width and height.  The
	       resource converter for this resource con-
	       structs bitmaps from the contents of files.
	       (See Converting Bitmaps for details.)  If
	       this bitmap is one bit deep then the 1's will
	       be rendered in the foreground color, and the
	       0's in the background color.  If bitmap has a
	       depth greater than one, it is copied directly
	       into the window.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

callback       A list of routines to be called when the
	       notify action is invoked.

colormap       The colormap that this widget will use.




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cornerRoundPercent
	       When a ShapeStyle of roundedRectangle is
	       used, this resource controls the radius of
	       the rounded corner.  The radius of the
	       rounded corners is specified as a percentage
	       of the length of the shortest side of the
	       widget.

cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.

cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will over-
	       ride the cursor resource if both are speci-
	       fied. (See 2.4.1)

decay	       The number of milliseconds that should be
	       subtracted from each succeeding interval
	       while the Repeater button is being held down
	       until the interval has reached minimumDelay
	       milliseconds.

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

encoding       The encoding method used by the value of the
	       label resource.	The value may be XawTextEn-
	       coding8bit or XawTextEncodingChar2b.  When
	       international is set to true this resource is
	       not used.

flash	       Whether or not to flash the Repeater button
	       whenever the timer goes off.

font	       The text font to use when displaying the
	       label, when the international resource is
	       false.

fontSet        The text font set to use when displaying the
	       label, when the international resource is
	       true.

foreground     A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       widget's window.  This color is also used to
	       render all 1's in a bitmap one plane deep.

height




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width	       The height and width of this widget in pix-
	       els.

highlightThickness
	       The thickness of the rectangle that is used
	       to highlight the internal border of this wid-
	       get, alerting the user that it is ready to be
	       selected.  The default value is 2 pixels if
	       the shapeStyle is rectangle, and 0 Pixels (no
	       highlighting) otherwise.

initialDelay   The number of milliseconds between the begin-
	       ning of the Repeater button being held down
	       and the first invocation of the callback
	       function.

insensitiveBorder
	       This pixmap will be tiled into the widget's
	       border if the widget becomes insensitive.

internalHeight
internalWidth  The minimum amount of space to leave between
	       the graphic and the vertical and horizontal
	       edges of the window.

international  This is a boolean flag, only settable at wid-
	       get creation time.  A value of false signals
	       the widget to use pre-R6 internationalization
	       (specifically, the lack thereof), such as
	       using fonts for displaying text, etc.  A
	       value of true directs the widget to act in an
	       internationalized manner, such as utilizing
	       font sets for displaying text, etc.

justify        Specifies left, center, or right alignment of
	       graphic within the widget.  This resource may
	       be specified with the values XtJustifyLeft,
	       XtJustifyCenter, or XtJustifyRight.  A con-
	       verter is registered for this resource that
	       will convert the following strings: left,
	       right, and center.  This resource only has
	       noticeable effect when the width of the wid-
	       get is larger than necessary to display the
	       graphic.  Note that when the graphic is a
	       multi-line label, the longest line will obey
	       this justification while shorter lines will
	       be left-justified with the longest one.


label	       Specifies the text string to be displayed in
	       the widget's window if no bitmap is speci-
	       fied.  The default is the name of this wid-
	       get.  Irregardless of the value of encoding
	       or international, a single newline character



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	       (1 byte) will cause a line break.

leftBitmap     Specifies a bitmap to display to the left of
	       the graphic in the widget's window.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

minimumDelay   The minimum time between callbacks in mil-
	       liseconds.

pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.

pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

repeatDelay    The number of milliseconds between each call-
	       back after the first (minus an increasing
	       number of decays).

resize	       Specifies whether the widget should attempt
	       to resize to its preferred dimensions when-
	       ever its resources are modified with XtSet-
	       Values.	This attempt to resize may be denied
	       by the parent of this widget.  The parent is
	       always free to resize the widget regardless
	       of the state of this resource.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

shapeStyle     Nonrectangular widgets may be created using
	       this resource.  Nonrectangular widgets are
	       supported only on a server that supports the
	       Shape Extension.  If nonrectangular widgets
	       are specified for a server lacking this
	       extension, the shape is ignored and the wid-
	       gets will be rectangular.  The following
	       shapes are currently supported: XmuShapeRect-
	       angle, XmuShapeOval, XmuShapeEllipse, and
	       XmuShapeRoundedRectangle.  A converter is



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	       registered for this resource that will con-
	       vert the following strings: rectangle, oval,
	       ellipse, and roundedRectangle.

startCallback  The list of functions to invoke by the start
	       action (typically when the Repeater button is
	       first pressed).	The callback data parameter
	       is set to NULL.

stopCallback   The list of functions to invoke by the stop
	       action (typically when the Repeater button is
	       released).  The callback data parameter is
	       set to NULL.

translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

3.6.2.	Repeater Actions

The Repeater widget supports the following actions beyond
those of the Command button:

start()        This invokes the functions on the startCall-
	       back and callback lists and sets a timer to
	       go off in initialDelay milliseconds.  The
	       timer will cause the callback functions to be
	       invoked with increasing frequency until the
	       stop action occurs.

stop()	       This invokes the functions on the stopCall-
	       back list and prevents any further timers
	       from occuring until the next start action.


The following are the default translation bindings used by
the Repeater widget:


     <EnterWindow>:   highlight()
     <LeaveWindow>:   unhighlight()
     <Btn1Down>:      set() start()
     <Btn1Up>:	      stop() unset()



3.7.  Scrollbar Widget



Application header file<X11/Xaw/Scrollbar.h>



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Class header file   <X11/Xaw/ScrollbarP.h>
Class		    scrollbarWidgetClass
Class Name	    Scrollbar
Superclass	    Simple



A Scrollbar widget is a rectangle, called the ``canvas,'' on
which another rectangle, the ``thumb,'' moves in one dimen-
sion, either vertically or horizontally.  A Scrollbar can be
used alone, as a value generator, or it can be used within a
composite widget (for example, a Viewport).  When a Scroll-
bar is used to move, or ``scroll,'' the contents of another
widget, the size and the position of the thumb usually give
feedback as to what portion of the other widget's contents
are visible.

Each pointer button invokes a specific action.	Pointer but-
tons 1 and 3 do not move the thumb automatically.  Instead,
they return the pixel position of the cursor on the scroll
region.  When pointer button 2 is clicked, the thumb moves
to the current pointer position.  When pointer button 2 is
held down and the pointer is moved, the thumb follows the
pointer.

The pointer cursor in the scroll region changes depending on
the current action.  When no pointer button is pressed, the
cursor appears as a double-headed arrow that points in the
direction that scrolling can occur.  When pointer button 1
or 3 is pressed, the cursor appears as a single-headed arrow
that points in the logical direction that the thumb will
move.  When pointer button 2 is pressed, the cursor appears
as an arrow that points to the top or the left of the thumb.

When the user scrolls, the application receives notification
through callback procedures.  For both discrete scrolling
actions, the callback returns the Scrollbar widget, the
client_data, and the pixel position of the pointer when the
button was released.  For continuous scrolling, the callback
routine returns the scroll bar widget, the client data, and
the current relative position of the thumb.  When the thumb
is moved using pointer button 2, the callback procedure is
invoked continuously.  When either button 1 or 3 is pressed,
the callback procedure is invoked only when the button is
released and the client callback procedure is responsible
for moving the thumb.

3.7.1.	Resources

When creating a Scrollbar widget instance, the following
resources are retrieved from the argument list or from the
resource database:





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----------------------------------------------------------------------------------------
Name		      Class	       Type	       NotesDefault Value
----------------------------------------------------------------------------------------
accelerators	      Accelerators     AcceleratorTable     NULL
ancestorSensitive     AncestorSensitiveBoolean	       D    True
background	      Background       Pixel		    XtDefaultBackground
backgroundPixmap      Pixmap	       Pixmap		    XtUnspecifiedPixmap
borderColor	      BorderColor      Pixel		    XtDefaultForeground
borderPixmap	      Pixmap	       Pixmap		    XtUnspecifiedPixmap
borderWidth	      BorderWidth      Dimension	    1
colormap	      Colormap	       Colormap 	    parent's Colormap
cursor		      Cursor	       Cursor		    None
cursorName	      Cursor	       String		    NULL
depth		      Depth	       int	       C    parent's Depth
destroyCallback       Callback	       XtCallbackList	    NULL
foreground	      Foreground       Pixel		    XtDefaultForeground
height		      Height	       Dimension       A    depends on orientation
insensitiveBorder     Insensitive      Pixmap		    GreyPixmap
international	      International    Boolean	       C    False
jumpProc	      Callback	       XtCallbackList	    NULL
length		      Length	       Dimension	    1
mappedWhenManaged     MappedWhenManagedBoolean		    True
minimumThumb	      MinimumThumb     Dimension	    7
orientation	      Orientation      Orientation	    XtorientVertical (vertical)
pointerColor	      Foreground       Pixel		    XtDefaultForeground
pointerColorBackgroundBackground       Pixel		    XtDefaultBackground
screen		      Screen	       Screen	       R    parent's Screen
scrollDCursor	      Cursor	       Cursor		    XC_sb_down_arrow
scrollHCursor	      Cursor	       Cursor		    XC_sb_h_double_arrow
scrollLCursor	      Cursor	       Cursor		    XC_sb_left_arrow
scrollProc	      Callback	       XtCallbackList	    NULL
scrollRCursor	      Cursor	       Cursor		    XC_sb_right_arrow
scrollUCursor	      Cursor	       Cursor		    XC_sb_up_arrow
scrollVCursor	      Cursor	       Cursor		    XC_sb_v_arrow
sensitive	      Sensitive        Boolean		    True
shown		      Shown	       Float		    0.0
thickness	      Thickness        Dimension	    14
thumb		      Thumb	       Bitmap		    GreyPixmap
thumbProc	      Callback	       XtCallbackList	    NULL
topOfThumb	      TopOfThumb       Float		    0.0
translations	      Translations     TranslationTable     See below
width		      Width	       Dimension       A    depends on orientation
x		      Position	       Position 	    0
y		      Position	       Position 	    0
----------------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).





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ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

colormap       The colormap that this widget will use.

cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.

cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will over-
	       ride the cursor resource if both are speci-
	       fied. (See 2.4.1)

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

foreground     A pixel value which indexes the widget's col-
	       ormap to derive the color used to draw the
	       thumb.

height




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width	       The height and width of this widget in pix-
	       els.

insensitiveBorder
	       This pixmap will be tiled into the widget's
	       border if the widget becomes insensitive.

international  This is a boolean flag, only settable at wid-
	       get creation time.  While not utilized in
	       this widget, it can and should be checked by
	       any subclasses that have behavior that should
	       vary with locale.

jumpProc       All functions on this callback list are
	       called when the NotifyThumb action is
	       invoked.  See the Scrollbar Actions section
	       for details.

length	       The height of a vertical scrollbar or the
	       width of a horizontal scrollbar.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

minimumThumb   The smallest size, in pixels, to which the
	       thumb can shrink.

orientation    The orientation is the direction that the
	       thumb will be allowed to move.  This value
	       can be either XtorientVertical or XtorientHo-
	       rizontal.  A converter is registered for this
	       resource that will convert the following
	       strings: vertical and horizontal.

pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.

pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

scrollDCursor  This cursor is used when scrolling backward
	       in a vertical scrollbar.





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scrollHCursor  This cursor is used when a horizontal scroll-
	       bar is inactive.

scrollLCursor  This cursor is used when scrolling forward in
	       a horizontal scrollbar.

scrollProc     All functions on this callback list may be
	       called when the NotifyScroll action is
	       invoked.  See the Scrollbar Actions section
	       for details.

scrollRCursor  This cursor is used when scrolling backward
	       in a horizontal scrollbar, or when thumbing a
	       vertical scrollbar.

scrollUCursor  This cursor is used when scrolling forward in
	       a vertical scrollbar, or when thumbing a hor-
	       izontal scrollbar.

scrollVCursor  This cursor is used when a vertical scrollbar
	       is inactive.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

shown	       This is the size of the thumb, expressed as a
	       percentage (0.0 - 1.0) of the length of the
	       scrollbar.

thickness      The width of a vertical scrollbar or the
	       height of a horizontal scrollbar.

thumb	       This pixmap is used to tile (or stipple) the
	       thumb of the scrollbar.	If no tiling is
	       desired, then set this resource to None.
	       This resource will accept either a bitmap or
	       a pixmap that is the same depth as the win-
	       dow.  The resource converter for this
	       resource constructs bitmaps from the contents
	       of files.  (See Converting Bitmaps for
	       details.)

topOfThumb     The location of the top of the thumb, as a
	       percentage (0.0 - 1.0) of the length of the
	       scrollbar.  This resource was called top in
	       previous versions of the Athena widget set.
	       The name collided with the a Form widget con-
	       straint resource, and had to be changed.

translations   The event bindings associated with this wid-
	       get.




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x
y	       The location of the upper left outside corner
	       of this widget in its parent.

3.7.2.	Scrollbar Actions

The actions supported by the Scrollbar widget are:

StartScroll(value)
	       The possible values are Forward, Backward, or
	       Continuous.  This must be the first action to
	       begin a new movement.

NotifyScroll(value)
	       The possible values are Proportional or Full-
	       Length.	If the argument to StartScroll was
	       Forward or Backward, NotifyScroll executes
	       the scrollProc callbacks and passes either;
	       the position of the pointer, if value is Pro-
	       portional, or the full length of the scroll
	       bar, if value is FullLength.  If the argument
	       to StartScroll was Continuous, NotifyScroll
	       returns without executing any callbacks.

EndScroll()    This must be the last action after a movement
	       is complete.

MoveThumb()    Repositions the Scrollbar's thumb to the cur-
	       rent pointer location.

NotifyThumb()
	       Calls the jumpProc callbacks and passes the
	       relative position of the pointer as a per-
	       centage of the scroll bar length.


The default bindings for Scrollbar are:


     <Btn1Down>: StartScroll(Forward)
     <Btn2Down>: StartScroll(Continuous) MoveThumb() NotifyThumb()
     <Btn3Down>: StartScroll(Backward)
     <Btn2Motion>:MoveThumb() NotifyThumb()
     <BtnUp>:	 NotifyScroll(Proportional) EndScroll()



Examples of additional bindings a user might wish to specify
in a resource file are:


*Scrollbar.Translations: \
     ~Meta<Key>space: StartScroll(Forward) NotifyScroll(FullLength) \n\
      Meta<Key>space: StartScroll(Backward) NotifyScroll(FullLength) \n\



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		      EndScroll()


3.7.3.	Scrollbar Callbacks

There are two callback lists provided by the Scrollbar wid-
get.  The procedural interface for these functions is
described here.

The calling interface to the scrollProc callback procedure
is:

void ScrollProc(scrollbar, client_data, position)
     Widget scrollbar;
     XtPointer client_data;
     XtPointer position;    /* int */


scrollbar Specifies the Scrollbar widget.

client_data
	  Specifies the client data.

position  Specifies a pixel position in integer form.

The scrollProc callback is used for incremental scrolling
and is called by the NotifyScroll action.  The position
argument is a signed quantity and should be cast to an int
when used. Using the default button bindings, button 1
returns a positive value, and button 3 returns a negative
value. In both cases, the magnitude of the value is the dis-
tance of the pointer in pixels from the top (or left) of the
Scrollbar. The value will never be greater than the length
of the Scrollbar.


The calling interface to the jumpProc callback procedure is:

void JumpProc(scrollbar, client_data, percent)
     Widget scrollbar;
     XtPointer client_data;
     XtPointer percent_ptr;    /* float* */


scrollbar Specifies the ID of the scroll bar widget.

client_data
	  Specifies the client data.

percent_ptr
	  Specifies the floating point position of the thumb
	  (0.0 - 1.0).





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The jumpProc callback is used to implement smooth scrolling
and is called by the NotifyThumb action.  Percent_ptr must
be cast to a pointer to float before use; i.e.


     float percent = *(float*)percent_ptr;


With the default button bindings, button 2 moves the thumb
interactively, and the jumpProc is called on each new posi-
tion of the pointer, while the pointer button remains down.
The value specified by percent_ptr is the current location
of the thumb (from the top or left of the Scrollbar)
expressed as a percentage of the length of the Scrollbar.

3.7.4.	Convenience Routines

To set the position and length of a Scrollbar thumb, use
XawScrollbarSetThumb.

void XawScrollbarSetThumb(w, top, shown)
     Widget w;
     float top;
     float shown;


w	  Specifies the Scrollbar widget.

top	  Specifies the position of the top of the thumb as
	  a fraction of the length of the Scrollbar.

shown	  Specifies the length of the thumb as a fraction of
	  the total length of the Scrollbar.

XawScrollbarThumb moves the visible thumb to a new position
(0.0 - 1.0) and length (0.0 - 1.0).  Either the top or shown
arguments can be specified as -1.0, in which case the cur-
rent value is left unchanged.  Values greater than 1.0 are
truncated to 1.0.

If called from jumpProc, XawScrollbarSetThumb has no effect.

3.7.5.	Setting Float Resources

The shown and topOfThumb resources are of type float.  These
resources can be difficult to get into an argument list.
The reason is that C performs an automatic cast of the float
value to an integer value, usually truncating the important
information.  The following code fragment is one portable
method of getting a float into an argument list.


	  top = 0.5;
	  if (sizeof(float) > sizeof(XtArgVal)) {



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	  /*
	   * If a float is larger than an XtArgVal then pass this
	   * resource value by reference.
	   */
		    XtSetArg(args[0], XtNshown, &top);
	  }
	  else {
	  /*
	   * Convince C not to perform an automatic conversion, which
	   * would truncate 0.5 to 0.
	   */
		    XtArgVal * l_top = (XtArgVal *) &top;
		    XtSetArg(args[0], XtNshown, *l_top);
	  }



3.8.  Simple Widget


Application Header file<Xaw/Simple.h>
Class Header file   <Xaw/SimpleP.h>
Class		    simpleWidgetClass
Class Name	    Simple
Superclass	    Core



The Simple widget is not very useful by itself, as it has no
semantics of its own.  It main purpose is to be used as a
common superclass for the other simple Athena widgets.	This
widget adds six resources to the resource list provided by
the Core widget and its superclasses.

3.8.1.	Resources

When creating a Simple widget instance, the following
resources are retrieved from the argument list or from the
resource database:


---------------------------------------------------------------------------------
Name		      Class	       Type	       NotesDefault Value
---------------------------------------------------------------------------------
accelerators	      Accelerators     AcceleratorTable     NULL
ancestorSensitive     AncestorSensitiveBoolean	       D    True
background	      Background       Pixel		    XtDefaultBackground
backgroundPixmap      Pixmap	       Pixmap		    XtUnspecifiedPixmap
borderColor	      BorderColor      Pixel		    XtDefaultForeground
borderPixmap	      Pixmap	       Pixmap		    XtUnspecifiedPixmap
borderWidth	      BorderWidth      Dimension	    1
colormap	      Colormap	       Colormap 	    Parent's Colormap
cursor		      Cursor	       Cursor		    None




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---------------------------------------------------------------------------------
Name		      Class	       Type	       NotesDefault Value
---------------------------------------------------------------------------------
cursorName	      Cursor	       String		    NULL
depth		      Depth	       int	       C    Parent's Depth
destroyCallback       Callback	       XtCallbackList	    NULL
height		      Height	       Dimension	    0
insensitiveBorder     Insensitive      Pixmap		    GreyPixmap
international	      International    Boolean	       C    False
mappedWhenManaged     MappedWhenManagedBoolean		    True
pointerColor	      Foreground       Pixel		    XtDefaultForeground
pointerColorBackgroundBackground       Pixel		    XtDefaultBackground
screen		      Screen	       Screen	       R    Parent's Screen
sensitive	      Sensitive        Boolean		    True
translations	      Translations     TranslationTable     NULL
width		      Width	       Dimension	    0
x		      Position	       Position 	    0
y		      Position	       Position 	    0
---------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.



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borderWidth    The width of this widget's window border.

colormap       The colormap that this widget will use.

cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.

cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will over-
	       ride the cursor resource if both are speci-
	       fied. (See 2.4.1)

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

height
width	       The height and width of this widget in pix-
	       els.

insensitiveBorder
	       This pixmap will be tiled into the widget's
	       border if the widget becomes insensitive.

international  This is a boolean flag, only settable at wid-
	       get creation time.  While not utilized in
	       this widget, it can and should be checked by
	       any subclasses that have behavior that should
	       vary with locale.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.

pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.





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sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

3.9.  StripChart Widget


Application Header file<Xaw/StripChart.h>
Class Header file   <Xaw/StripCharP.h>
Class		    stripChartWidgetClass
Class Name	    StripChart
Superclass	    Simple



The StripChart widget is used to provide a roughly real time
graphical chart of a single value.  For example, it is used
by the common client program xload to provide a graph of
processor load.  The StripChart reads data from an applica-
tion, and updates the chart at the update interval speci-
fied.

3.9.1.	Resources

When creating a StripChart widget instance, the following
resources are retrieved from the argument list or from the
resource database:


-----------------------------------------------------------------------------------------
Name		      Class	       Type	       NotesDefault Value
-----------------------------------------------------------------------------------------
accelerators	      Accelerators     AcceleratorTable     NULL
ancestorSensitive     AncestorSensitiveBoolean	       D    True
background	      Background       Pixel		    XtDefaultBackground
backgroundPixmap      Pixmap	       Pixmap		    XtUnspecifiedPixmap
borderColor	      BorderColor      Pixel		    XtDefaultForeground
borderPixmap	      Pixmap	       Pixmap		    XtUnspecifiedPixmap
borderWidth	      BorderWidth      Dimension	    1
colormap	      Colormap	       Colormap 	    Parent's Colormap
cursor		      Cursor	       Cursor		    None
cursorName	      Cursor	       String		    NULL
depth		      Depth	       int	       C    Parent's Depth
destroyCallback       Callback	       XtCallbackList	    NULL
foreground	      Foreground       Pixel		    XtDefaultForeground




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-----------------------------------------------------------------------------------------
Name		      Class	       Type	       NotesDefault Value
-----------------------------------------------------------------------------------------
getValue	      Callback	       XtCallbackList	    NULL
height		      Height	       Dimension	    120
highlight	      Foreground       Pixel		    XtDefaultForeground
insensitiveBorder     Insensitive      Pixmap		    GreyPixmap
international	      International    Boolean	       C    False
jumpScroll	      JumpScroll       int	       A    half the width of the widget
mappedWhenManaged     MappedWhenManagedBoolean		    True
minScale	      Scale	       int		    1
pointerColor	      Foreground       Pixel		    XtDefaultForeground
pointerColorBackgroundBackground       Pixel		    XtDefaultBackground
screen		      Screen	       Pointer	       R    Parent's Screen
sensitive	      Sensitive        Boolean		    True
translations	      Translations     TranslationTable     NULL
update		      Interval	       int		    10
width		      Width	       Dimension	    120
x		      Position	       Position 	    0
y		      Position	       Position 	    0
-----------------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap



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	       specified will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

colormap       The colormap that this widget will use.

cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.

cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will over-
	       ride the cursor resource if both are speci-
	       fied. (See 2.4.1)

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

foreground     A pixel value which indexes the widget's col-
	       ormap to derive the color that will be used
	       to draw the graph.

getValue       A list of callback functions to call every
	       update seconds.	This list should contain one
	       function, which returns the value to be
	       graphed by the StripChart widget.  The fol-
	       lowing section describes the procedural
	       interface.  Behavior when this list has more
	       than one function is undefined.

height
width	       The height and width of this widget in pix-
	       els.

highlight      A pixel value which indexes the widget's col-
	       ormap to derive the color that will be used
	       to draw the scale lines on the graph.

insensitiveBorder
	       This pixmap will be tiled into the widget's
	       border if the widget becomes insensitive.

international  This is a boolean flag, only settable at wid-
	       get creation time.  While not utilized in
	       this widget, it can and should be checked by
	       any subclasses that have behavior that should
	       vary with locale.





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jumpScroll     When the graph reaches the right edge of the
	       window it must be scrolled to the left.	This
	       resource specifies the number of pixels it
	       will jump.  Smooth scrolling can be achieved
	       by setting this resource to 1.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

minScale       The minimum scale for the graph.  The number
	       of divisions on the graph will always be
	       greater than or equal to this value.

pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.

pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

translations   The event bindings associated with this wid-
	       get.

update	       The number of seconds between graph updates.
	       Each update is represented on the graph as a
	       1 pixel wide line.  Every update seconds the
	       getValue procedure will be used to get a new
	       graph point, and this point will be added to
	       the right end of the StripChart.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

3.9.2.	Getting the StripChart Value

The StripChart widget will call the application routine
passed to it as the getValue callback function every update
seconds to obtain another point for the StripChart graph.




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The calling interface for the getValue callback is:

void (*getValueProc)(w, client_data, value)
     Widget w;
     XtPointer client_data;
     XtPointer value;	 /* double * */


w	  Specifies the StripChart widget.

client_data
	  Specifies the client data.

value	  Returns a pointer to a double.  The application
	  should set the address pointed to by this argument
	  to a double containing the value to be graphed on
	  the StripChart.

This function is used by the StripChart to call an applica-
tion routine.  The routine will pass the value to be graphed
back to the the StripChart in the value field of this rou-
tine.


3.10.  Toggle Widget


Application Header file<Xaw/Toggle.h>
Class Header file   <Xaw/ToggleP.h>
Class		    toggleWidgetClass
Class Name	    Toggle
Superclass	    Command



The Toggle widget is an area, often rectangular, that dis-
plays a graphic.  The graphic may be a text string contain-
ing multiple lines of characters in an 8 bit or 16 bit char-
acter set (to be displayed with a font), or in a multi-byte
encoding (for use with a fontset).  The graphic may also be
a bitmap or pixmap.

This widget maintains a Boolean state (e.g.  True/False or
On/Off) and changes state whenever it is selected.  When the
pointer is on the Toggle widget, the Toggle widget may
become highlighted by drawing a rectangle around its perime-
ter.  This highlighting indicates that the Toggle widget is
ready for selection.  When pointer button 1 is pressed and
released, the Toggle widget indicates that it has changed
state by reversing its foreground and background colors, and
its notify action is invoked, calling all functions on its
callback list.	If the pointer is moved off of the widget
before the pointer button is released, the Toggle widget
reverts to its previous foreground and background colors,



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Athena Widget Set			    X11, Release 6.4


and releasing the pointer button has no effect.  This behav-
ior allows the user to cancel the operation.

Toggle widgets may also be part of a ``radio group.''  A
radio group is a list of at least two Toggle widget in which
no more than one Toggle may be set at any time.  A radio
group is identified by the widget ID of any one of its mem-
bers.  The convenience routine XawToggleGetCurrent will
return information about the Toggle widget in the radio
group.

Toggle widget state is preserved across changes in sensitiv-
ity.

3.10.1.  Resources

When creating a Toggle widget instance, the following
resources are retrieved from the argument list or from the
resource database:


-------------------------------------------------------------------------------------------------
Name		      Class		Type		NotesDefault Value
-------------------------------------------------------------------------------------------------
accelerators	      Accelerators	AcceleratorTable     NULL
ancestorSensitive     AncestorSensitive Boolean 	D    True
background	      Background	Pixel		     XtDefaultBackground
backgroundPixmap      Pixmap		Pixmap		     XtUnspecifiedPixmap
bitmap		      Bitmap		Pixmap		     None
borderColor	      BorderColor	Pixel		     XtDefaultForeground
borderPixmap	      Pixmap		Pixmap		     XtUnspecifiedPixmap
borderWidth	      BorderWidth	Dimension	     1
callback	      Callback		XtCallbackList	     NULL
colormap	      Colormap		Colormap	     Parent's Colormap
cornerRoundPercent    CornerRoundPercentDimension	     25
cursor		      Cursor		Cursor		     None
cursorName	      Cursor		String		     NULL
depth		      Depth		int		C    Parent's Depth
destroyCallback       Callback		XtCallbackList	     NULL
encoding	      Encoding		UnsignedChar	     XawTextEncoding8bit
font		      Font		XFontStruct	     XtDefaultFont
fontSet 	      FontSet		XFontSet	     XtDefaultFontSet
foreground	      Foreground	Pixel		     XtDefaultForeground
height		      Height		Dimension	A    graphic height + 2 * internalHeight
highlightThickness    Thickness 	Dimension	A    2 (0 if Shaped)
insensitiveBorder     Insensitive	Pixmap		     GreyPixmap
internalHeight	      Height		Dimension	     2
internalWidth	      Width		Dimension	     4
international	      International	Boolean 	C    False
justify 	      Justify		Justify 	     XtJustifyCenter (center)
label		      Label		String		     name of widget
leftBitmap	      LeftBitmap	Bitmap		     None
mappedWhenManaged     MappedWhenManaged Boolean 	     True




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-------------------------------------------------------------------------------------------------
Name		      Class		Type		NotesDefault Value
-------------------------------------------------------------------------------------------------
pointerColor	      Foreground	Pixel		     XtDefaultForeground
pointerColorBackgroundBackground	Pixel		     XtDefaultBackground
radioData	      RadioData 	Pointer 	     Name of widget
radioGroup	      Widget		Widget		     No radio group
resize		      Resize		Boolean 	     True
screen		      Screen		Screen		R    Parent's Screen
sensitive	      Sensitive 	Boolean 	     True
shapeStype	      ShapeStyle	ShapeStyle	     Rectangle
state		      State		Boolean 	     Off
translations	      Translations	TranslationTable     See below
width		      Width		Dimension	A    graphic width + 2 * internalWidth
x		      Position		Position	     0
y		      Position		Position	     0
-------------------------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

bitmap	       A bitmap to display instead of the label.
	       The default size of the widget will be just
	       large enough to contain the bitmap and the
	       widget's internal width and height.  The
	       resource converter for this resource con-
	       structs bitmaps from the contents of files.
	       (See Converting Bitmaps for details.)  If
	       this bitmap is one bit deep then the 1's will
	       be rendered in the foreground color, and the
	       0's in the background color.  If bitmap has a
	       depth greater than one, it is copied directly



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	       into the window.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

callback       A list of routines to be called when the
	       notify action is invoked.

colormap       The colormap that this widget will use.

cornerRoundPercent
	       When a ShapeStyle of roundedRectangle is
	       used, this resource controls the radius of
	       the rounded corner.  The radius of the
	       rounded corners is specified as a percentage
	       of the length of the shortest side of the
	       widget.

cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.

cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will over-
	       ride the cursor resource if both are speci-
	       fied. (See 2.4.1)

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

encoding       The encoding method used by the value of the
	       label resource.	The value may be XawTextEn-
	       coding8bit or XawTextEncodingChar2b.  When
	       international is set to true this resource is
	       not used.

font	       The text font to use when displaying the
	       label, when the international resource is
	       false.





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fontSet        The text font set to use when displaying the
	       label, when the international resource is
	       true.

foreground     A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       widget's window.  This color is also used to
	       render all 1's in a bitmap one plane deep.

height
width	       The height and width of this widget in pix-
	       els.

highlightThickness
	       The thickness of the rectangle that is used
	       to highlight the internal border of this wid-
	       get, alerting the user that it is ready to be
	       selected.  The default value is 2 pixels if
	       the shapeStyle is rectangle, and 0 Pixels (no
	       highlighting) otherwise.

insensitiveBorder
	       This pixmap will be tiled into the widget's
	       border if the widget becomes insensitive.

internalHeight
internalWidth  The minimum amount of space to leave between
	       the graphic and the vertical and horizontal
	       edges of the window.

international  This is a boolean flag, only settable at wid-
	       get creation time.  A value of false signals
	       the widget to use pre-R6 internationalization
	       (specifically, the lack thereof), such as
	       using fonts for displaying text, etc.  A
	       value of true directs the widget to act in an
	       internationalized manner, such as utilizing
	       font sets for displaying text, etc.

justify        Specifies left, center, or right alignment of
	       graphic within the widget.  This resource may
	       be specified with the values XtJustifyLeft,
	       XtJustifyCenter, or XtJustifyRight.  A con-
	       verter is registered for this resource that
	       will convert the following strings: left,
	       right, and center.  This resource only has
	       noticeable effect when the width of the wid-
	       get is larger than necessary to display the
	       graphic.  Note that when the graphic is a
	       multi-line label, the longest line will obey
	       this justification while shorter lines will
	       be left-justified with the longest one.





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label	       Specifies the text string to be displayed in
	       the widget's window if no bitmap is speci-
	       fied.  The default is the name of this wid-
	       get.  Irregardless of the value of encoding
	       or international, a single newline character
	       (1 byte) will cause a line break.

leftBitmap     Specifies a bitmap to display to the left of
	       the graphic in the widget's window.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.

pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

radioData      Specifies the data that will be returned by
	       XawToggleGetCurrent when this is the cur-
	       rently set widget in the radio group.  This
	       value is also used to identify the Toggle
	       that will be set by a call to XawToggle-
	       SetCurrent.  The value NULL will be returned
	       by XawToggleGetCurrent if no widget in a
	       radio group is currently set.  Programmers
	       must not specify NULL (or Zero) as radioData.

radioGroup     Specifies another Toggle widget that is in
	       the radio group to which this Toggle widget
	       should be added.  A radio group is a group of
	       at least two Toggle widgets, only one of
	       which may be set at a time.  If this value is
	       NULL (the default) then the Toggle will not
	       be part of any radio group and can change
	       state without affecting any other Toggle wid-
	       gets.  If the widget specified in this
	       resource is not already in a radio group then
	       a new radio group will be created containing
	       these two Toggle widgets.  No Toggle widget
	       can be in multiple radio groups.  The behav-
	       ior of a radio group of one toggle is unde-
	       fined.  A converter is registered which will
	       convert widget names to widgets without
	       caching.




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resize	       Specifies whether the widget should attempt
	       to resize to its preferred dimensions when-
	       ever its resources are modified with XtSet-
	       Values.	This attempt to resize may be denied
	       by the parent of this widget.  The parent is
	       always free to resize the widget regardless
	       of the state of this resource.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

shapeStyle     Nonrectangular widgets may be created using
	       this resource.  Nonrectangular widgets are
	       supported only on a server that supports the
	       Shape Extension.  If nonrectangular widgets
	       are specified for a server lacking this
	       extension, the shape is ignored and the wid-
	       gets will be rectangular.  The following
	       shapes are currently supported: XmuShapeRect-
	       angle, XmuShapeOval, XmuShapeEllipse, and
	       XmuShapeRoundedRectangle.  A converter is
	       registered for this resource that will con-
	       vert the following strings: rectangle, oval,
	       ellipse, and roundedRectangle.

state	       Specifies whether the Toggle widget is set
	       (True) or unset (False).

translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

3.10.2.  Toggle Actions

The Toggle widget supports the following actions:

o    Switching the Toggle widget between the foreground and
     background colors with set and unset and toggle

o    Processing application callbacks with notify

o    Switching the internal border between highlighted and
     unhighlighted states with highlight and unhighlight

The following are the default translation bindings used by
the Toggle widget:



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     <EnterWindow>:   highlight(Always)
     <LeaveWindow>:   unhighlight()
     <Btn1Down>,<Btn1Up>:toggle() notify()


3.10.3.  Toggle Actions

The full list of actions supported by Toggle is:

highlight(condition)
	       Displays the internal highlight border in the
	       color (foreground or background ) that con-
	       trasts with the interior color of the Toggle
	       widget.	The conditions WhenUnset and Always
	       are understood by this action procedure.  If
	       no argument is passed then WhenUnset is
	       assumed.

unhighlight()  Displays the internal highlight border in the
	       color (foreground or background ) that
	       matches the interior color of the Toggle wid-
	       get.

set()	       Enters the set state, in which notify is pos-
	       sible.  This action causes the Toggle widget
	       to display its interior in the foreground
	       color.  The label or bitmap is displayed in
	       the background color.

unset()        Cancels the set state and displays the inte-
	       rior of the Toggle widget in the background
	       color.  The label or bitmap is displayed in
	       the foreground color.

toggle()       Changes the current state of the Toggle wid-
	       get, causing to be set if it was previously
	       unset, and unset if it was previously set.
	       If the widget is to be set, and is in a radio
	       group then this procedure may unset another
	       Toggle widget causing all routines on its
	       callback list to be invoked.  The callback
	       routines for the Toggle that is to be unset
	       will be called before the one that is to be
	       set.

reset()        Cancels any set or highlight and displays the
	       interior of the Toggle widget in the back-
	       ground color, with the label displayed in the
	       foreground color.

notify()       When the Toggle widget is in the set state
	       this action calls all functions in the call-
	       back list named by the callback resource.
	       The value of the call_data argument in these



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	       callback functions is undefined.


			    Note

     When a bitmap of depth greater that one (1) is
     specified the set(), unset(), and reset() actions
     have no effect, since there are no foreground and
     background colors used in a multi-plane pixmap.


3.10.4.  Radio Groups

There are typically two types of radio groups desired by
applications.  The default translations for the Toggle wid-
get implement a "zero or one of many" radio group.  This
means that there may be no more than one Toggle widget
active, but there need not be any Toggle widgets active.

The other type of radio group is "one of many" and has the
more strict policy that there will always be exactly one
radio button active.  Toggle widgets can be used to provide
this interface with a slight modification to the translation
table of each Toggle in the group.


     <EnterWindow>:   highlight(Always)
     <LeaveWindow>:   unhighlight()
     <Btn1Down>,<Btn1Up>:set() notify()


This translation table will not allow any Toggle to be unset
except as a result of another Toggle becoming set.  It is
the application programmer's responsibility to choose an
initial state for the radio group by setting the state
resource of one of its member widgets to True.

3.10.5.  Convenience Routines

The following functions allow easy access to the Toggle wid-
get's radio group functionality.

3.10.5.1.  Changing the Toggle's Radio Group.

To enable an application to change the Toggle's radio group,
add the Toggle to a radio group, or remove the Toggle from a
radio group, use XawToggleChangeRadioGroup.

void XawToggleChangeRadioGroup(w, radio_group)
     Widget w, radio_group;


w	  Specifies the Toggle widget.




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radio_group
	  Specifies any Toggle in the new radio group.	If
	  NULL then the Toggle will be removed from any
	  radio group of which it is a member.

If a Toggle is already set in the new radio group, and the
Toggle to be added is also set then the previously set Tog-
gle in the radio group is unset and its callback procedures
are invoked.

Finding the Currently selected Toggle in a radio group of
Toggles

To find the currently selected Toggle in a radio group of
Toggle widgets use XawToggleGetCurrent.

XtPointer XawToggleGetCurrent(radio_group);
     Widget radio_group;


radio_group
	  Specifies any Toggle widget in the radio group.

The value returned by this function is the radioData of the
Toggle in this radio group that is currently set.  The
default value for radioData is the name of that Toggle wid-
get.  If no Toggle is set in the radio group specified then
NULL is returned.

Changing the Toggle that is set in a radio group.

To change the Toggle that is currently set in a radio group
use XawToggleSetCurrent.

void XawToggleSetCurrent(radio_group, radio_data);
     Widget radio_group;
     XtPointer radio_data;


radio_group
	  Specifies any Toggle widget in the radio group.

radio_data
	  Specifies the radioData identifying the Toggle
	  that should be set in the radio group specified by
	  the radio_group argument.

XawToggleSetCurrent locates the Toggle widget to be set by
matching radio_data against the radioData for each Toggle in
the radio group.  If none match, XawToggleSetCurrent returns
without making any changes.  If more than one Toggle
matches, XawToggleSetCurrent will choose a Toggle to set
arbitrarily.  If this causes any Toggle widgets to change
state, all routines in their callback lists will be invoked.



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Athena Widget Set			    X11, Release 6.4


The callback routines for a Toggle that is to be unset will
be called before the one that is to be set.

Unsetting all Toggles in a radio group.

To unset all Toggle widgets in a radio group use XawToggle-
UnsetCurrent.

void XawToggleUnsetCurrent(radio_group);
     Widget radio_group;


radio_group
	  Specifies any Toggle widget in the radio group.

If this causes a Toggle widget to change state, all routines
on its callback list will be invoked.








































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			 Chapter 4

			   Menus




The Athena widget set provides support for single paned non-
hierarchical popup and pulldown menus.	Since menus are such
a common user interface tool, support for them must be pro-
vided in even the most basic widget sets.  In menuing as in
other areas, the Athena Widget Set provides only basic func-
tionality.

Menus in the Athena widget set are implemented as a menu
container (the SimpleMenu widget) and a collection of
objects that comprise the menu entries.  The SimpleMenu wid-
get is itself a direct subclass of the OverrideShell widget
class, so no other shell is necessary when creating a menu.
The managed children of a SimpleMenu must be subclasses of
the Sme (Simple Menu Entry) object.

The Athena widget set provides three classes of Sme objects
that may be used to build menus.


Sme	  The base class of all menu entries.  It may be
	  used as a menu entry itself to provide blank space
	  in a menu.  ``Sme'' means ``Simple Menu Entry.''

SmeBSB	  This menu entry provides a selectable entry con-
	  taining a text string.  A bitmap may also be
	  placed in the left and right margins.  ``BSB''
	  means ``Bitmap String Bitmap.''

SmeLine   This menu entry provides an unselectable entry
	  containing a separator line.


The SimpleMenu widget informs the window manager that it
should ignore its window by setting the Override Redirect
flag.  This is the correct behavior for the press-drag-
release style of menu operation.  If click-move-click or
``pinable''' menus are desired it is the responsibility of
the application programmer, using the SimpleMenu resources,
to inform the window manager of the menu.

To allow easy creation of pulldown menus, a MenuButton wid-
get is also provided as part of the Athena widget set.






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4.1.  Using the Menus

The default configuration for the menus is press-drag-
release.  The menus will typically be activated by clicking
a pointer button while the pointer is over a MenuButton,
causing the menu to appear in a fixed location relative to
that button; this is a pulldown menu.  Menus may also be
activated when a specific pointer and/or key sequence is
used anywhere in the application; this is a popup menu (e.g.
clicking Ctrl-<pointer button 1> in the common application
xterm).  In this case the menu should be positioned under
the cursor. Typically menus will be placed so the pointer
cursor is on the first menu entry, or the last entry
selected by the user.

The menu remains on the screen as long as the pointer button
is held down.  Moving the pointer will highlight different
menu items.  If the pointer leaves the menu, or moves over
an entry that cannot be selected then no menu entry will
highlighted.  When the desired menu entry has been high-
lighted, releasing the pointer button removes the menu, and
causes any mechanism associated with this entry to be
invoked.

4.2.  SimpleMenu Widget


Application Header file<X11/Xaw/SimpleMenu.h>
Class Header file   <X11/Xaw/SimpleMenP.h>
Class		    simpleMenuWidgetClass
Class Name	    SimpleMenu
Superclass	    OverrideShell



The SimpleMenu widget is a container for the menu entries.
It is a direct subclass of shell, and is should be created
with XtCreatePopupShell, not XtCreateManagedWidget.  This is
the only part of the menu that actually is associated with a
window.  The SimpleMenu serves as the glue to bind the indi-
vidual menu entries together into a menu.

4.2.1.	Resources


The resources associated with the SimpleMenu widget control
aspects that will affect the entire menu.

-------------------------------------------------------------------------------------------------------------
Name		       Class		      Type		 Notes	 Default Value
-------------------------------------------------------------------------------------------------------------
accelerators	       Accelerators	      AcceleratorTable		 NULL
ancestorSensitive      AncestorSensitive      Boolean		 D	 True




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-------------------------------------------------------------------------------------------------------------
Name		       Class		      Type		 Notes	 Default Value
-------------------------------------------------------------------------------------------------------------
allowShellResize       AllowShellResize       Boolean			 True
background	       Background	      Pixel			 XtDefaultBackground
backgroundPixmap       Pixmap		      Pixmap			 XtUnspecifiedPixmap
backingStore	       BackingStore	      BackingStore		 see below
borderColor	       BorderColor	      Pixel			 XtDefaultForeground
borderPixmap	       Pixmap		      Pixmap			 XtUnspecifiedPixmap
borderWidth	       BorderWidth	      Dimension 		 1
bottomMargin	       VerticalMargins	      Dimension 		 0
children	       ReadOnly 	      WidgetList	 R	 NULL
createPopupChildProc   CreatePopupChildProc   Function			 NULL
colormap	       Colormap 	      Colormap			 Parent's Colormap
cursor		       Cursor		      Cursor			 None
depth		       Depth		      int		 C	 Parent's Depth
destroyCallback        Callback 	      XtCallbackList		 NULL
geometry	       Geometry 	      String			 NULL
height		       Height		      Dimension 		 Enough space to contain all entries
label		       Label		      String			 NULL
labelClass	       LabelClass	      Pointer			 SmeBSBObjectClass
mappedWhenManaged      MappedWhenManaged      Boolean			 True
menuOnScreen	       MenuOnScreen	      Boolean			 True
numChildren	       ReadOnly 	      Cardinal		 R	 0
overrideRedirect       OverrideRedirect       Boolean			 True
popdownCallback        Callback 	      XtCallbackList		 NULL
popupCallback	       Callback 	      XtCallbackList		 NULL
popupOnEntry	       PopupOnEntry	      Widget		 A	 Label or first entry
rowHeight	       RowHeight	      Dimension 		 0
saveUnder	       SaveUnder	      Boolean			 False
screen		       Screen		      Screen		 R	 Parent's Screen
sensitive	       Sensitive	      Boolean			 True
topMargin	       VerticalMargins	      Dimension 		 0
translations	       Translations	      TranslationTable		 See below
visual		       Visual		      Visual			 CopyFromParent
width		       Width		      Dimension 		 Width of widest entry
x		       Position 	      Position			 0
y		       Position 	      Position			 0
-------------------------------------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.




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backingStore   Determines what type of backing store will be
	       used for the menu.  Legal values for this
	       resource are NotUseful, WhenMapped, and
	       Always.	These values are the backing-store
	       integers defined in <X11/X.h>.  A converter
	       is registered for this resource that will
	       convert the following strings: notUseful,
	       whenMapped, always, and default.  If default
	       is specified (the default behavior) the
	       server will use whatever it thinks is appro-
	       priate.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

bottomMargin
topMargin      The amount of space between the top or bottom
	       of the menu and the menu entry closest to
	       that edge.

children       A list of all this composite widget's current
	       children.

colormap       The colormap that this widget will use.

cursor	       The shape of the mouse pointer whenever it is
	       in this widget.

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.




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geometry       If this resource is specified it will over-
	       ride the x, y, width and height of this wid-
	       get.  The format of this string is
	       [<width>x<height>][{+ -} <xoffset> {+
	       -}<yoffset>].

height
width	       The height and width of this widget in pix-
	       els.

label	       This label will be placed at the top of the
	       SimpleMenu, and may not be highlighted.	The
	       name of the label object is menuLabel.  Using
	       this name it is possible to modify the
	       label's attributes through the resource
	       database.  When the label is created, the
	       label is hard coded to the value of label,
	       and justify is hard coded as XtJustifyCenter.

labelClass     Specifies the type of Sme object created as
	       the menu label.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

menuOnScreen   If the menu is automatically positioned under
	       the cursor with the XawPositionSimpleMenu
	       action, and this resource is True, then the
	       menu will always be fully visible on the
	       screen.

numChildren    The number of children in this composite wid-
	       get.

overrideRedirect
	       Determines the value of the override_redirect
	       attribute of the SimpleMenu's window.  The
	       override_redirect attribute of a window
	       determines whether or not a window manager
	       may interpose itself between this window and
	       the root window of the display.	For more
	       information see the Interclient Communica-
	       tions Conventions Manual.

popdownCallback
popupCallback  These callback functions are called by the Xt
	       Intrinsics whenever the shell is popped up or
	       down (See X Toolkit Intrinsics -- C Language
	       Interface for details).

popupOnEntry   The XawPositionSimpleMenu action will, by
	       default, popup the SimpleMenu with its label



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	       (or first entry) directly under the pointer.
	       To popup the menu under another entry, set
	       this resource to the menu entry that should
	       be under the pointer, when the menu is popped
	       up.  This allows the application to offer the
	       user a default menu entry that can be
	       selected with out moving the pointer.

rowHeight      If this resources is zero (the default) then
	       each menu entry will be given its desired
	       height.	If this resource has any other value
	       then all menu entries will be forced to be
	       rowHeight pixels high.

saveUnder      If this is True then save unders will be
	       active on the menu's window.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

4.2.2.	SimpleMenu Actions

The SimpleMenu widget supports the following actions:

o    Switching the entry under the mouse pointer between the
     foreground and background colors with highlight and
     unhighlight

o    Processing menu entry callbacks with notify


The following are the default translation bindings used by
the SimpleMenu widget:



     <EnterWindow>:   highlight()
     <LeaveWindow>:   unhighlight()
     <BtnMotion>:     highlight()
     <BtnUp>:	      MenuPopdown() notify() unhighlight()





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The user can pop down the menu without activating any of the
callback functions by releasing the pointer button when no
menu item is highlighted.


The full list of actions supported by SimpleMenu is:

highlight()    Highlight the menu entry that is currently
	       under the pointer.  Only a item that is high-
	       lighted will be notified when the notify
	       action is invoked.  The look of a highlighted
	       entry is determined by the menu entry.

unhighlight()  Unhighlights the currently highlighted menu
	       item, and returns it to its normal look.

notify()       Notifies the menu entry that is currently
	       highlighted that is has been selected.  It is
	       the responsibility of the menu entry to take
	       the appropriate action.

MenuPopdown(menu)
	       This action is defined in X Toolkit Intrin-
	       sics -- C Language Interface.

4.2.3.	Positioning the SimpleMenu

If the SimpleMenu widget is to be used as a pulldown menu
then the MenuButton widget, or some other outside means
should be used to place the menu when it is popped up.

If popup menus are desired it will be necessary to add the
XawPositionSimpleMenu and MenuPopup actions to the transla-
tion table of the widget that will be popping up the menu.
The MenuPopup action is described in X Toolkit Intrinsics --
C Language Interface.  XawPositionSimpleMenu is a global
action procedure registered by the SimpleMenu widget when
the first one is created or the convenience routine XawSim-
pleMenuAddGlobalActions is called.

Translation writers should be aware that Xt does not regis-
ter grabs on ``don't care'' modifiers, and therefore the
left hand side of the production should be written to
exclude unspecified modifiers.	For example these are the
translations needed to popup some of xterm's menus:



     !Ctrl<Btn1Down>: XawPositionSimpleMenu(xterm) MenuPopup(xterm)
     !Ctrl<Btn2Down>: XawPositionSimpleMenu(modes) MenuPopup(modes)







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XawPositionSimpleMenu(menu)
		      The XawPositionSimpleMenu routine will
		      search for the menu name passed to it
		      using XtNameToWidget starting with the
		      widget invoking the action as the ref-
		      erence widget.  If it is unsuccessful
		      it will continue up the widget tree
		      using each of the invoking widget's
		      ancestors as the reference widget.  If
		      it is still unsuccessful it will print
		      a warning message and give up.  XawPo-
		      sitionSimpleMenu will position the
		      menu directly under the pointer cur-
		      sor.  The menu will be placed so that
		      the pointer cursor is centered on the
		      entry named by the popupOnEntry
		      resource.  If the menuOnScreen
		      resource is True then the menu will
		      always be fully visible on the screen.

4.2.4.	Convenience Routines

4.2.4.1.  Registering the Global Action Routines

The XawPositionSimpleMenu action routine may often be
invoked before any menus have been created.  This can occur
when an application uses dynamic menu creation.  In these
cases an application will need to register this global
action routine by calling XawSimpleMenuAddGlobalActions:

void XawSimpleMenuAddGlobalActions(app_con)
      XtAppContext app_con;


app_con   Specifies the application context in which this
	  action should be registered.

This function need only be called once per application and
must be called before any widget that uses XawPositionSim-
pleMenu action is realized.

4.2.4.2.  Getting and Clearing the Current Menu Entry

To get the currently highlighted menu entry use XawSimple-
MenuGetActiveEntry:

Widget XawSimpleMenuGetActiveEntry(w)
      Widget w;


w	  Specifies the SimpleMenu widget.

This function returns the menu entry that is currently high-
lighted, or NULL if no entry is highlighted.



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To clear the SimpleMenu widget's internal information about
the currently highlighted menu entry use XawSimpleMenuClear-
ActiveEntry:

Widget XawSimpleMenuClearActiveEntry(w)
      Widget w;


w	  Specifies the SimpleMenu widget.

This function unsets all internal references to the cur-
rently highlighted menu entry.	It does not unhighlight or
otherwise alter the appearance of the active entry.  This
function is primarily for use by implementors of menu
entries.

4.3.  SmeBSB Object



Application Header file<X11/Xaw/SmeBSB.h>
Class Header file   <X11/Xaw/SmeBSBP.h>
Class		    smeBSBObjectClass
Class Name	    SmeBSB
Superclass	    Sme



The SmeBSB object is used to create a menu entry that con-
tains a string, and optional bitmaps in its left and right
margins.  Since each menu entry is an independent object,
the application is able to change the font, color, height,
and other attributes of the menu entries, on an entry by
entry basis.  The format of the string may either be the
encoding of the 8 bit font utilized, or in a multi-byte
encoding for use with a fontSet.

4.3.1.	Resources

The resources associated with the SmeBSB object are defined
in this section, and affect only the single menu entry spec-
ified by this object.

-----------------------------------------------------------------------------------------
Name		    Class		Type		 Notes	 Default Value
-----------------------------------------------------------------------------------------
ancestorSensitive   AncestorSensitive	Boolean 	 D	 True
callback	    Callback		Callback		 NULL
destroyCallback     Callback		XtCallbackList		 NULL
font		    Font		FontStruct		 XtDefaultFont
fontSet 	    FontSet		XFontSet		 XtDefaultFontSet
foreground	    Foreground		Pixel			 XtDefaultForeground
height		    Height		Dimension	 A	 Font height + vertSpace




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-----------------------------------------------------------------------------------------
Name		    Class		Type		 Notes	 Default Value
-----------------------------------------------------------------------------------------
international	    International	Boolean 	 C	 False
justify 	    Justify		Justify 		 XtjustifyLeft
label		    Label		String			 NULL
leftBitmap	    LeftBitmap		Pixmap			 XtUnspecifiedPixmap
leftMargin	    leftMargin		Dimension		 4
rightBitmap	    RightBitmap 	Pixmap			 XtUnspecifiedPixmap
rightMargin	    rightMargin 	Dimension		 4
sensitive	    Sensitive		Boolean 		 True
vertSpace	    VertSpace		int			 25
width		    Width		Dimension	 A	 TextWidth + margins
-----------------------------------------------------------------------------------------


ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

callback       All callback functions on this list are
	       called when the SimpleMenu notifies this
	       entry that the user has selected it.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

font	       The text font to use when displaying the
	       label, when the international resource is
	       false.

fontSet        The text font set to use when displaying the
	       label, when the international resource is
	       true.

foreground     A pixel value which indexes the SimpleMenu's
	       colormap to derive the foreground color of
	       the menu entry's window.  This color is also
	       used to render all 1's in the left and right
	       bitmaps.

height
width	       The height and width of this widget in pix-
	       els.  Keep in mind that the SimpleMenu widget
	       will force the width of all menu entries to
	       be the width of the longest entry.

international  This is a boolean flag, only settable at wid-
	       get creation time.  A value of false signals
	       the widget to use pre-R6 internationalization



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	       (specifically, the lack thereof), such as
	       using fonts for displaying text, etc.  A
	       value of true directs the widget to act in an
	       internationalized manner, such as utilizing
	       font sets for displaying text, etc.

justify        How the label is to be rendered between the
	       left and right margins when the space is
	       wider than the actual text.  This resource
	       may be specified with the values XtJusti-
	       fyLeft, XtJustifyCenter, or XtJustifyRight.
	       When specifying the justification from a
	       resource file the values left, center, or
	       right may be used.

label	       This is a the string that will be displayed
	       in the menu entry.  The exact location of
	       this string within the bounds of the menu
	       entry is controlled by the leftMargin, right-
	       Margin, vertSpace, and justify resources.

leftBitmap
rightBitmap    This is a name of a bitmap to display in the
	       left or right margin of the menu entry.	All
	       1's in the bitmap will be rendered in the
	       foreground color, and all 0's will be drawn
	       in the background color of the SimpleMenu
	       widget.	It is the programmers' responsibil-
	       ity to make sure that the menu entry is tall
	       enough, and the appropriate margin wide
	       enough to accept the bitmap.  If care is not
	       taken the bitmap may extend into another menu
	       entry, or into this entry's label.

leftMargin
rightMargin    This is the amount of space (in pixels) that
	       will be left between the edge of the menu
	       entry and the label string.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

vertSpace      This is the amount of vertical padding,
	       expressed as a percentage of the height of
	       the font, that is to be placed around the
	       label of a menu entry.. The label and bitmaps
	       are always centered vertically within the
	       menu.  The default value for this resource
	       (25) causes the default height to be 125% of
	       the height of the font.





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4.4.  SmeLine Object



Application Header file<X11/Xaw/SmeLine.h>
Class Header file   <X11/Xaw/SmeLineP.h>
Class		    smeLineObjectClass
Class Name	    SmeLine
Superclass	    Sme



The SmeLine object is used to add a horizontal line or menu
separator to a menu.  Since each SmeLine is an independent
object, the application is able to change the color, height,
and other attributes of the SmeLine objects on an entry by
entry basis.  This object is not selectable, and will not
highlight when the pointer cursor is over it.

4.4.1.	Resources

The resources associated with the SmeLine object are defined
in this section, and affect only the single menu entry spec-
ified by this object.

--------------------------------------------------------------------------------
Name		  Class 	  Type		   Notes   Default Value
--------------------------------------------------------------------------------
destroyCallback   Callback	  XtCallbackList	   NULL
foreground	  Foreground	  Pixel 		   XtDefaultForeground
height		  Height	  Dimension		   lineWidth
international	  International   Boolean	   C	   False
lineWidth	  LineWidth	  Dimension		   1
stipple 	  Stipple	  Pixmap		   XtUnspecifiedPixmap
width		  Width 	  Dimension		   1
--------------------------------------------------------------------------------


destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

foreground     A pixel value which indexes the SimpleMenu's
	       colormap to derive the foreground color used
	       to draw the separator line.

height
width	       The height and width of this widget in pix-
	       els.  Keep in mind that the SimpleMenu widget
	       will force all menu items to be the width of
	       the widest entry.  Thus, setting the width is
	       generally not very important.





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international  This is a boolean flag, only settable at wid-
	       get creation time.  While not utilized in
	       this widget, it can and should be checked by
	       any subclasses that have behavior that should
	       vary with locale.

lineWidth      The width of the horizontal line that is to
	       be displayed.

stipple        If a bitmap is specified for this resource,
	       the line will be stippled through it.  This
	       allows the menu separator to be rendered as
	       something more exciting than just a line.
	       For instance, if you define a stipple that is
	       a chain link, then your menu separators will
	       look like chains.

4.5.  Sme Object



Application Header file<X11/Xaw/Sme.h>
Class Header file   <X11/Xaw/SmeP.h>
Class		    smeObjectClass
Class Name	    Sme
Superclass	    RectObj



The Sme object is the base class for all menu entries.
While this object is mainly intended to be subclassed, it
may be used in a menu to add blank space between menu
entries.

4.5.1.	Resources

The resources associated with the SmeLine object are defined
in this section, and affect only the single menu entry spec-
ified by this object.  There are no new resources added for
this class, as it picks up all its resources from the Rec-
tObj class.

--------------------------------------------------------------------------------------
Name		    Class		Type		 Notes	 Default Value
--------------------------------------------------------------------------------------
ancestorSensitive   AncestorSensitive	Boolean 		 True
callback	    Callback		XtCallbackList		 NULL
destroyCallback     Callback		XtCallbackList		 NULL
height		    Height		Dimension		 0
international	    International	Boolean 	 C	 False
sensitive	    Sensitive		Boolean 		 True
width		    Width		Dimension		 1
--------------------------------------------------------------------------------------




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ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

height
width	       The height and width of this widget in pix-
	       els.  Keep in mind that the SimpleMenu widget
	       will force all menu items to be the width of
	       the widest entry.

international  This is a boolean flag, only settable at wid-
	       get creation time.  While not utilized in
	       this widget, it can and should be checked by
	       any subclasses that have behavior that should
	       vary with locale.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

4.5.2.	Subclassing the Sme Object


To Create a new Sme object class you will need to define
three class methods.  These methods allow the SimpleMenu to
highlight and unhighlight the menu entry as the pointer cur-
sor moves over it, as well as notify the entry when the user
has selected it.  All of these methods may be inherited from
the Sme object, although the default semantics are not very
interesting.

Highlight()
	  Called to put the menu entry into the highlighted
	  state.

Unhighlight()
	  Called to return the widget to its normal (unhigh-
	  lighted) state.

Notify()  Called when the user selects this menu entry.


Other then these methods, creating a new object is straight
forward.  Here is some information that may help you avoid
some common mistakes.




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1) Objects can be zero pixels high.

2) Objects draw on their parent's window, therefore the
   Drawing dimensions are different from those of widgets.
   For instance, y locations vary from y to y + height, not
   0 to height.

3) XtSetValues calls may come from the application while the
   Sme is highlighted, and if the SetValues method returns
   True, will result in an expose event.  The SimpleMenu may
   later call the menu entry's unhighlight procedure.  How-
   ever, due to the asynchronous nature of X, the expose
   event generated by XtSetValues will come after this
   unhighlight.

4) Remember that your subclass of the Sme does not own the
   window.  Share the space with other menu entries, and
   refrain from drawing outside the subclass's own section
   of the menu.


4.6.  MenuButton Widget


Application Header file<X11/Xaw/MenuButton.h>
Class Header file   <X11/Xaw/MenuButtonP.h>
Class		    menuButtonWidgetClass
Class Name	    MenuButton
Superclass	    Command



The MenuButton widget is an area, often rectangular, that
displays a graphic.  The graphic may be a text string con-
taining multiple lines of characters in an 8 bit or 16 bit
character set (to be displayed with a font), or in a multi-
byte encoding (for use with a fontset).  The graphic may
also be a bitmap or pixmap.

When the pointer cursor is on a MenuButton widget, the
MenuButton becomes highlighted by drawing a rectangle around
its perimeter.	This highlighting indicates that the
MenuButton is ready for selection.  When a pointer button is
pressed, the MenuButton widget will pop up the menu named in
the menuName resource.

4.6.1.	Resources

When creating a MenuButton widget instance, the following
resources are retrieved from the argument list or from the
resource database:






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-------------------------------------------------------------------------------------------------
Name		      Class		Type		NotesDefault Value
-------------------------------------------------------------------------------------------------
accelerators	      Accelerators	AcceleratorTable     NULL
ancestorSensitive     AncestorSensitive Boolean 	D    True
background	      Background	Pixel		     XtDefaultBackground
backgroundPixmap      Pixmap		Pixmap		     XtUnspecifiedPixmap
bitmap		      Bitmap		Pixmap		     None
borderColor	      BorderColor	Pixel		     XtDefaultForeground
borderPixmap	      Pixmap		Pixmap		     XtUnspecifiedPixmap
borderWidth	      BorderWidth	Dimension	     1
callback	      Callback		XtCallbackList	     NULL
colormap	      Colormap		Colormap	     Parent's Colormap
cornerRoundPercent    CornerRoundPercentDimension	     25
cursor		      Cursor		Cursor		     None
cursorName	      Cursor		String		     None
depth		      Depth		int		C    Parent's Depth
destroyCallback       Callback		XtCallbackList	     NULL
encoding	      Encoding		UnsignedChar	     XawTextEncoding8bit
font		      Font		XFontStruct	     XtDefaultFont
fontSet 	      FontSet		XFontSet	     XtDefaultFontSet
foreground	      Foreground	Pixel		     XtDefaultForeground
height		      Height		Dimension	A    graphic height + 2 * internalHeight
highlightThickness    Thickness 	Dimension	A    2 (0 if Shaped)
insensitiveBorder     Insensitive	Pixmap		     GreyPixmap
internalHeight	      Height		Dimension	     2
internalWidth	      Width		Dimension	     4
international	      International	Boolean 	C    False
justify 	      Justify		Justify 	     XtJustifyCenter (center)
label		      Label		String		     name of widget
leftBitmap	      LeftBitmap	Bitmap		     None
mappedWhenManaged     MappedWhenManaged Boolean 	     True
menuName	      MenuName		String		     "menu"
pointerColor	      Foreground	Pixel		     XtDefaultForeground
pointerColorBackgroundBackground	Pixel		     XtDefaultBackground
resize		      Resize		Boolean 	     True
screen		      Screen		Screen		R    Parent's Screen
sensitive	      Sensitive 	Boolean 	     True
shapeStype	      ShapeStyle	ShapeStyle	     Rectangle
translations	      Translations	TranslationTable     See below
width		      Width		Dimension	A    graphic width + 2 * internalWidth
x		      Position		Position	     0
y		      Position		Position	     0
-------------------------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of



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	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

bitmap	       A bitmap to display instead of the label.
	       The default size of the widget will be just
	       large enough to contain the bitmap and the
	       widget's internal width and height.  The
	       resource converter for this resource con-
	       structs bitmaps from the contents of files.
	       (See Converting Bitmaps for details.)  If
	       this bitmap is one bit deep then the 1's will
	       be rendered in the foreground color, and the
	       0's in the background color.  If bitmap has a
	       depth greater than one, it is copied directly
	       into the window.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

callback       A list of routines to be called when the
	       notify action is invoked.

colormap       The colormap that this widget will use.

cornerRoundPercent
	       When a ShapeStyle of roundedRectangle is
	       used, this resource controls the radius of
	       the rounded corner.  The radius of the
	       rounded corners is specified as a percentage
	       of the length of the shortest side of the
	       widget.




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cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.

cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will over-
	       ride the cursor resource if both are speci-
	       fied. (See 2.4.1)

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

font	       The text font to use when displaying the
	       label, when the international resource is
	       false.

fontSet        The text font set to use when displaying the
	       label, when the international resource is
	       true.

foreground     A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       widget's window.  This color is also used to
	       render all 1's in a bitmap one plane deep.

height
width	       The height and width of this widget in pix-
	       els.

highlightThickness
	       The thickness of the rectangle that is used
	       to highlight the internal border of this wid-
	       get, alerting the user that it is ready to be
	       selected.  The default value is 2 pixels if
	       the shapeStyle is rectangle, and 0 Pixels (no
	       highlighting) otherwise.

insensitiveBorder
	       This pixmap will be tiled into the widget's
	       border if the widget becomes insensitive.

internalHeight
internalWidth  The minimum amount of space to leave between
	       the graphic and the vertical and horizontal
	       edges of the window.

international  This is a boolean flag, only settable at wid-
	       get creation time.  A value of false signals
	       the widget to use pre-R6 internationalization
	       (specifically, the lack thereof), such as



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	       using fonts for displaying text, etc.  A
	       value of true directs the widget to act in an
	       internationalized manner, such as utilizing
	       font sets for displaying text, etc.

justify        Specifies left, center, or right alignment of
	       graphic within the widget.  This resource may
	       be specified with the values XtJustifyLeft,
	       XtJustifyCenter, or XtJustifyRight.  A con-
	       verter is registered for this resource that
	       will convert the following strings: left,
	       right, and center.  This resource only has
	       noticeable effect when the width of the wid-
	       get is larger than necessary to display the
	       graphic.  Note that when the graphic is a
	       multi-line label, the longest line will obey
	       this justification while shorter lines will
	       be left-justified with the longest one.


label	       Specifies the text string to be displayed in
	       the widget's window if no bitmap is speci-
	       fied.  The default is the name of this wid-
	       get.  Irregardless of the value of encoding
	       or international, a single newline character
	       (1 byte) will cause a line break.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

menuName       The name of a popup shell to popup as a menu.
	       The MenuButton will search for this name
	       using XtNameToWidget starting with itself as
	       the reference widget.  If the search is
	       unsuccessful the widget will continue up the
	       widget tree using each of its ancestors as
	       the reference widget passed to XtNameToWid-
	       get.  If no widget of called menuName is
	       found by this algorithm, the widget will
	       print a warning message and give up.  When
	       the menu is found it will be popped up exclu-
	       sive and spring_loaded.	The MenuButton wid-
	       get does not copy the value of this resource
	       into newly allocated memory. The application
	       programmer must pass the resource value in
	       nonvolatile memory.

pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.




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pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

resize	       Specifies whether the widget should attempt
	       to resize to its preferred dimensions when-
	       ever its resources are modified with XtSet-
	       Values.	This attempt to resize may be denied
	       by the parent of this widget.  The parent is
	       always free to resize the widget regardless
	       of the state of this resource.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

shapeStyle     Nonrectangular widgets may be created using
	       this resource.  Nonrectangular widgets are
	       supported only on a server that supports the
	       Shape Extension.  If nonrectangular widgets
	       are specified for a server lacking this
	       extension, the shape is ignored and the wid-
	       gets will be rectangular.  The following
	       shapes are currently supported: XmuShapeRect-
	       angle, XmuShapeOval, XmuShapeEllipse, and
	       XmuShapeRoundedRectangle.  A converter is
	       registered for this resource that will con-
	       vert the following strings: rectangle, oval,
	       ellipse, and roundedRectangle.

translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

4.6.2.	MenuButton Actions

The MenuButton widget supports the following actions:

o    Switching the button between the foreground and back-
     ground colors with set and unset

o    Processing application callbacks with notify

o    Switching the internal border between highlighted and
     unhighlighted states with highlight and unhighlight



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o    Popping up a menu with PopupMenu

The following are the default translation bindings used by
the MenuButton widget:



     <EnterWindow>:   highlight()
     <LeaveWindow>:   reset()
     <BtnDown>:       reset() PopupMenu(


4.6.3.	MenuButton Actions

The full list of actions supported by MenuButton is:

highlight(condition)
	       Displays the internal highlight border in the
	       color (foreground or background ) that con-
	       trasts with the interior color of the Command
	       widget.	The conditions WhenUnset and Always
	       are understood by this action procedure.  If
	       no argument is passed, WhenUnset is assumed.

unhighlight()  Displays the internal highlight border in the
	       color (XtNforeground or background ) that
	       matches the interior color of the MenuButton
	       widget.

set()	       Enters the set state, in which notify is pos-
	       sible.  This action causes the button to dis-
	       play its interior in the foreground color.
	       The label or bitmap is displayed in the back-
	       ground color.

unset()        Cancels the set state and displays the inte-
	       rior of the button in the background color.
	       The label or bitmap is displayed in the fore-
	       ground color.

reset()        Cancels any set or highlight and displays the
	       interior of the button in the background
	       color, with the label displayed in the fore-
	       ground color.

notify()       When the button is in the set state this
	       action calls all functions in the callback
	       list named by the callback resource.  The
	       value of the call_data argument in these
	       callback functions is undefined.

PopupMenu()    Pops up the menu specified by the menuName
	       resource.




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The MenuButton widget does not place a server grab on
itself.  Instead, PopupMenu is registered as a grab action.
As a result, clients which popup menus without using
XtMenuPopup or MenuPopup or PopupMenu in translations will
fail to have a grab active.  They should make a call to
XtRegisterGrabAction on the appropriate action in the appli-
cation initialization routine, or use a different transla-
tion.

















































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			 Chapter 5

			Text Widgets




The Text widget provides a window that will allow an appli-
cation to display and edit one or more lines of text.
Options are provided to allow the user to add Scrollbars to
its window, search for a specific string, and modify the
text in the buffer.

The Text widget is made up of a number of pieces; it was
modularized to ease customization.  The AsciiText widget
class (actually not limited to ASCII but so named for com-
patibility) is be general enough to most needs.  If more
flexibility, special features, or extra functionality is
needed, they can be added by implementing a new TextSource
or TextSink, or by subclassing the Text Widget (See Section
5.8 for customization details.)

The words insertion point are used in this chapter to refer
to the text caret.  This is the symbol that is displayed
between two characters in the file.  The insertion point
marks the location where any new characters will be added to
the file.  To avoid confusion the pointer cursor will always
be referred to as the pointer.

The text widget supports three edit modes, controlling the
types of modifications a user is allowed to make:

o    Append-only

o    Editable

o    Read-only

Read-only mode does not allow the user or the programmer to
modify the text in the widget.	While the entire string may
be reset in read-only mode with XtSetValues, it cannot be
modified via with XawTextReplace.  Append-only and editable
modes allow the text at the insertion point to be modified.
The only difference is that text may only be added to or
removed from the end of a buffer in append-only mode.


5.1.  Text Widget for Users

The Text widget provides many of the common keyboard editing
commands.  These commands allow users to move around and
edit the buffer.  If an illegal operation is attempted,



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(such as deleting characters in a read-only text widget),
the X server will beep.

5.1.1.	Default Key Bindings

The default key bindings are patterned after those in the
EMACS text editor:


Ctrl-a	  Beginning Of Line   Meta-b	     Backward Word
Ctrl-b	  Backward Character  Meta-f	     Forward Word
Ctrl-d	  Delete Next Character 	     Meta-iInsert File
Ctrl-e	  End Of Line	      Meta-k	     Kill To End Of Paragraph
Ctrl-f	  Forward Character   Meta-q	     Form Paragraph
Ctrl-g	  Multiply Reset      Meta-v	     Previous Page
Ctrl-h	  Delete Previous Character	     Meta-yInsert Current Selection
Ctrl-j	  Newline And Indent  Meta-z	     Scroll One Line Down
Ctrl-k	  Kill To End Of Line Meta-d	     Delete Next Word
Ctrl-l	  Redraw Display      Meta-D	     Kill Word
Ctrl-m	  Newline	      Meta-h	     Delete Previous Word
Ctrl-n	  Next Line	      Meta-H	     Backward Kill Word
Ctrl-o	  Newline And Backup  Meta-<	     Beginning Of File
Ctrl-p	  Previous Line       Meta->	     End Of File
Ctrl-r	  Search/Replace Backward	     Meta-]Forward Paragraph
Ctrl-s	  Search/Replace Forward	     Meta-[Backward Paragraph
Ctrl-t	  Transpose Characters
Ctrl-u	  Multiply by 4       Meta-Delete    Delete Previous Word
Ctrl-v	  Next Page	      Meta-Shift DeleteKill Previous Word
Ctrl-w	  Kill Selection      Meta-Backspace Delete Previous Word
Ctrl-y	  Unkill	      Meta-Shift BackspaceKill Previous Word
Ctrl-z	  Scroll One Line Up
Ctrl-\	  Reconnect to input method
Kanji	  Reconnect to input method



In addition, the pointer may be used to cut and paste text:


	  Button 1 Down  Start Selection
	  Button 1 MotionAdjust Selection
	  Button 1 Up	 End Selection (cut)

	  Button 2 Down  Insert Current Selection (paste)

	  Button 3 Down  Extend Current Selection
	  Button 3 MotionAdjust Selection
	  Button 3 Up	 End Selection (cut)



Since all of these key and pointer bindings are set through
the translations and resource manager, the user and the
application programmer can modify them by changing the Text



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widget's translations resource.

5.1.2.	Search and Replace

The Text widget provides a search popup that can be used to
search for a string within the current Text widget.  The
popup can be activated by typing either Control-r or Con-
trol-s.  If Control-s is used the search will be forward in
the file from the current location of the insertion point;
if Control-r is used the search will be backward.  The acti-
vated popup is placed under the pointer.  It has a number of
buttons that allow both text searches and text replacements
to be performed.

At the top of the search popup are two toggle buttons
labeled backward and forward.  One of these buttons will
always be highlighted; this is the direction in which the
search will be performed.  The user can change the direction
at any time by clicking on the appropriate button.

Directly under the buttons there are two text areas, one
labeled Search for: and the other labeled Replace with:.  If
this is a read-only Text widget the Replace with: field will
be insensitive and no replacements will be allowed.  After
each of these labels will be a text field.  This field will
allow the user to enter a string to search for and the
string to replace it with.  Only one of these text fields
will have a window border around it; this is the active text
field.	Any key presses that occur when the focus in in the
search popup will be directed to the active text field.
There are also a few special key sequences:

     Carriage Return: Execute the action, and pop down the search widget.
     Tab:	      Execute the action, then move to the next field.
     Shift Carriage Return:Execute the action, then move to the next field.
     Control-q Tab:   Enter a Tab into a text field.
     Control-c:       Pop down the search popup.


Using these special key sequences should allow simple
searches without ever removing one's hands from the key-
board.

Near the bottom of the search popup is a row of buttons.
These buttons allow the same actions to to be performed as
the key sequences, but the buttons will leave the popup
active.  This can be quite useful if many searches are being
performed, as the popup will be left on the display.  Since
the search popup is a transient window, it may be picked up
with the window manager and pulled off to the side for use
at a later time.

Search	       Search for the specified string.




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Replace        Replace the currently highlighted string with
	       the string in the Replace with text field,
	       and move onto the next occurrence of the
	       Search for text field.  The functionality is
	       commonly referred to as query-replace.

Replace-All    Replace all occurrences of the search string
	       with the replace string from the current
	       insertion point position to the end (or
	       beginning) of the file.	There is no key
	       sequence to perform this action.

Cancel	       Remove the search popup from the screen.

Finally, when international resource is true, there may be a
pre-edit buffer below the button row, for composing input.
Its presence is determined by the X locale in use and the
VendorShell's preeditType resource.

The widget hierarchy for the search popup is show below, all
widgets are listed by class and instance name.

Text  <name of Text widget>
     TransientShell  search
	  Form	form
	       Label label1
	       Label  label2
	       Toggle  backwards
	       Toggle  forwards
	       Label  searchLabel
	       Text  searchText
	       Label  replaceLabel
	       Text  replaceText
	       Command	search
	       Command	replaceOne
	       Command	replaceAll
	       Command	cancel

5.1.3.	File Insertion

To insert a file into a text widget, type the key sequence
Meta-i, which will activate the file insert popup.  This
popup will appear under the pointer, and any text typed
while the focus is in this popup will be redirected to the
text field used for the filename.  When the desired filename
has been entered, click on Insert File, or type Carriage
Return.  The named file will then be inserted in the text
widget beginning at the insertion point position.  If an
error occurs when opening the file, an error message will be
printed, prompting the user to enter the filename again.
The file insert may be aborted by clicking on Cancel.  If
Meta-i is typed at a text widget that is read-only, it will
beep, as no file insertion is allowed.




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The widget hierarchy for the file insert popup is show
below; all widgets are listed by class and instance name.

Text  <name of Text widget>
     TransientShell  insertFile
	  Form	form
	       Label  label
	       Text  text
	       Command	insert
	       Command	cancel

5.1.4.	Text Selections for Users

The text widgets have a text selection mechanism that allows
the user to copy pieces of the text into the PRIMARY selec-
tion, and paste into the text widget some text that another
application (or text widget) has put in the PRIMARY selec-
tion.

One method of selecting text is to press pointer button 1 on
the beginning of the text to be selected, drag the pointer
until all of the desired text is highlighted, and then
release the button to activate the selection.  Another
method is to click pointer button 1 at one end of the text
to be selected, then click pointer button 3 at the other
end.

To modify a currently active selection, press pointer button
3 near either the end of the selection that you want to
adjust.  This end of the selection may be moved while hold-
ing down pointer button 3.  When the proper area has been
highlighted release the pointer button to activate the
selection.

The selected text may now be pasted into another applica-
tion, and will remain active until some other client makes a
selection.  To paste text that some other application has
put into the PRIMARY selection use pointer button 2.  First
place the insertion point where you would like the text to
be inserted, then click and release pointer button 2.

Rapidly clicking pointer button 1 the following number of
times will adjust the selection as described.

Two	  Select the word under the pointer.  A word bound-
	  ary is defined by the Text widget to be a Space,
	  Tab, or Carriage Return.

Three	  Select the line under the pointer.

Four	  Select the paragraph under the pointer.  A para-
	  graph boundary is defined by the text widget as
	  two Carriage Returns in a row with only Spaces or
	  Tabs between them.



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Five	  Select the entire text buffer.

To unset the text selection, click pointer button 1 without
moving it.

5.2.  Text Widget Actions


All editing functions are performed by translation manager
actions that may be specified through the translations
resource in the Text widget.



Insert Point Movement	 Delete
     forward-character	      delete-next-character
     backward-character       delete-previous-character
     forward-word	      delete-next-word
     backward-word	      delete-previous-word
     forward-paragraph	      delete-selection
     backward-paragraph
     beginning-of-line
     end-of-line	 Selection
     next-line		      select-word
     previous-line	      select-all
     next-page		      select-start
     previous-page	      select-adjust
     beginning-of-file	      select-end
     end-of-file	      extend-start
     scroll-one-line-up       extend-adjust
     scroll-one-line-down     extend-end
			      insert-selection


Miscellaneous		 New Line
     redraw-display	      newline-and-indent
     insert-file	      newline-and-backup
     insert-char	      newline
     insert-string
     display-caret
     focus-in		 Kill
     focus-in		      kill-word
     search		      backward-kill-word
     multiply		      kill-selection
     form-paragraph	      kill-to-end-of-line
     transpose-characters     kill-paragraph
     no-op		      kill-to-end-of-paragraph
     XawWMProtocols
     reconnect-im



Most of the actions take no arguments, and unless otherwise
noted you may assume this to be the case.



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5.2.1.	Cursor Movement Actions



forward-character()
backward-character()
		    These actions move the insert point for-
		    ward or backward one character in the
		    buffer.  If the insert point is at the
		    end or beginning of a line this action
		    will move the insert point to the next
		    (or previous) line.

forward-word()
backward-word()     These actions move the insert point to
		    the next or previous word boundary.  A
		    word boundary is defined as a Space, Tab
		    or Carriage Return.

forward-paragraph()
backward-paragraph()
		    These actions move the insert point to
		    the next or previous paragraph boundary.
		    A paragraph boundary is defined as two
		    Carriage Returns in a row with only
		    Spaces or Tabs between them.

beginning-of-line()
end-of-line()	    These actions move to the beginning or
		    end of the current line.  If the insert
		    point is already at the end or beginning
		    of the line then no action is taken.

next-line()
previous-line()     These actions move the insert point up
		    or down one line.  If the insert point
		    is currently N characters from the
		    beginning of the line then it will be N
		    characters from the beginning of the
		    next or previous line.  If N is past the
		    end of the line, the insert point is
		    placed at the end of the line.

next-page()
previous-page()     These actions move the insert point up
		    or down one page in the file.  One page
		    is defined as the current height of the
		    text widget.  The insert point is always
		    placed at the first character of the top
		    line by this action.

beginning-of-file()
end-of-file()	    These actions place the insert point at
		    the beginning or end of the current text



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		    buffer.  The text widget is then
		    scrolled the minimum amount necessary to
		    make the new insert point location visi-
		    ble.

scroll-one-line-up()
scroll-one-line-down()
		    These actions scroll the current text
		    field up or down by one line.  They do
		    not move the insert point.	Other than
		    the scrollbars this is the only way that
		    the insert point may be moved off of the
		    visible text area.	The widget will be
		    scrolled so that the insert point is
		    back on the screen as soon as some other
		    action is executed.

5.2.2.	Delete Actions



delete-next-character()
delete-previous-character()
		    These actions remove the character imme-
		    diately before or after the insert
		    point.  If a Carriage Return is removed
		    then the next line is appended to the
		    end of the current line.

delete-next-word()
delete-previous-word()
		    These actions remove all characters
		    between the insert point location and
		    the next word boundary.  A word boundary
		    is defined as a Space, Tab or Carriage
		    Return.

delete-selection()  This action removes all characters in
		    the current selection.  The selection
		    can be set with the selection actions.

5.2.3.	Selection Actions



select-word()	    This action selects the word in which
		    the insert point is currently located.
		    If the insert point is between words
		    then it will select the previous word.

select-all()	    This action selects the entire text
		    buffer.





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select-start()	    This action sets the insert point to the
		    current pointer location (if triggered
		    by a button event) or text cursor loca-
		    tion (if triggered by a key event).  It
		    will then begin a selection at this
		    location.  If many of these selection
		    actions occur quickly in succession then
		    the selection count mechanism will be
		    invoked (see the section titled Text
		    Selections for Application Programmers
		    for details).

select-adjust()     This action allows a selection started
		    with the select-start action to be modi-
		    fied, as described above.

select-end(name[,name,...])
		    This action ends a text selection that
		    began with the select-start action, and
		    asserts ownership of the selection or
		    selections specified.  A name can be a
		    selection (e.g., PRIMARY) or a cut
		    buffer (e.g., CUT_BUFFER0).  Note that
		    case is important.	If no names are
		    specified, PRIMARY is asserted.

extend-start()	    This action finds the nearest end of the
		    current selection, and moves it to the
		    current pointer location (if triggered
		    by a button event) or text cursor loca-
		    tion (if triggered by a key event).

extend-adjust()     This action allows a selection started
		    with an extend-start action to be modi-
		    fied.

extend-end(name[,name,...])
		    This action ends a text selection that
		    began with the extend-start action, and
		    asserts ownership of the selection or
		    selections specified.  A name can be a
		    selection (e.g. PRIMARY) or a cut buffer
		    (e.g CUT_BUFFER0).	Note that case is
		    important.	If no names are given, PRI-
		    MARY is asserted.

insert-selection(name[,name,...])
		    This action retrieves the value of the
		    first (left-most) named selection that
		    exists or the cut buffer that is not
		    empty and inserts it into the Text wid-
		    get at the current insert point loca-
		    tion. A name can be a selection (e.g.
		    PRIMARY) or a cut buffer (e.g



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		    CUT_BUFFER0).  Note that case is impor-
		    tant.

5.2.4.	The New Line Actions



newline-and-indent()
		    This action inserts a newline into the
		    text and adds spaces to that line to
		    indent it to match the previous line.

newline-and-backup()
		    This action inserts a newline into the
		    text after the insert point.

newline()	    This action inserts a newline into the
		    text before the insert point.

5.2.5.	Kill and Actions



kill-word()
backward-kill-word()
		    These actions act exactly like the
		    delete-next-word and delete-previous-
		    word actions, but they stuff the word
		    that was killed into the kill buffer
		    (CUT_BUFFER_1).

kill-selection()    This action deletes the current selec-
		    tion and stuffs the deleted text into
		    the kill buffer (CUT_BUFFER_1).

kill-to-end-of-line()
		    This action deletes the entire line to
		    the right of the insert point position,
		    and stuffs the deleted text into the
		    kill buffer (CUT_BUFFER_1).

kill-paragraph()    This action deletes the current para-
		    graph, if between paragraphs it deletes
		    the paragraph above the insert point,
		    and stuffs the deleted text into the
		    kill buffer (CUT_BUFFER_1).

kill-to-end-of-paragraph()
		    This action deletes everything between
		    the current insert point location and
		    the next paragraph boundary, and stuffs
		    the deleted text into the kill buffer
		    (CUT_BUFFER_1).




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5.2.6.	Miscellaneous Actions



redraw-display()    This action recomputes the location of
		    all the text lines on the display,
		    scrolls the text to vertically center
		    the line containing the insert point on
		    the screen, clears the entire screen,
		    and redisplays it.

insert-file([filename])
		    This action activates the insert file
		    popup.  The filename option specifies
		    the default filename to put in the file-
		    name buffer of the popup.  If no file-
		    name is specified the buffer is empty at
		    startup.

insert-char()	    This action may only be attached to a
		    key event. When the international
		    resource is false, this action calls
		    XLookupString to translate the event
		    into a (rebindable) Latin-1 character
		    (sequence) and inserts it into the text
		    at the insert point.  When the interna-
		    tional resource is true, characters are
		    passed to the input method via
		    XwcLookupString, and any committed
		    string returned is inserted into the
		    text at the insert point.

insert-string(string[,string,...])
		    This action inserts each string into the
		    text at the insert point location.	Any
		    string beginning with the characters
		    "0x" followed by an even number of hex-
		    adecimal digits is interpreted as a hex-
		    adecimal constant and the corresponding
		    string is inserted instead.  This hex-
		    adecimal string may represent up to 50
		    8-bit characters.
		     When theinternational resource is true,
		    a hexadecimal string is intrepeted as
		    being in a multi-byte encoding, and a
		    hexadecimal or regular string will
		    result in an error message if it is not
		    legal in the current locale.

display-caret(state,when)
		    This action allows the insert point to
		    be turned on and off.  The state argu-
		    ment specifies the desired state of the
		    insert point.  This value may be any of



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		    the string values accepted for Boolean
		    resources (e.g. on, True, off, False,
		    etc.).  If no arguments are specified,
		    the default value is True.	The when
		    argument specifies, for EnterNotify or
		    LeaveNotify events whether or not the
		    focus field in the event is to be exam-
		    ined.  If the second argument is not
		    specified, or specified as something
		    other than always then if the action is
		    bound to an  EnterNotify or LeaveNotify
		    event, the action will be taken only if
		    the focus field is True.  An augmented
		    binding that might be useful is:


		    *Text.Translations: #override \
			 <FocusIn>:	display-caret(on) \n\
			 <FocusOut>:	display-caret(off)


focus-in()
focus-out()	    These actions do not currently do any-
		    thing.

search(direction,[string])
		    This action activates the search popup.
		    The direction must be specified as
		    either forward or backward.  The string
		    is optional and is used as an initial
		    value for the Search for: string.  For
		    further explanation of the search widget
		    see the section on Text Searches.

multiply(value)     The multiply action allows the user to
		    multiply the effects of many of the text
		    actions.  Thus the following action
		    sequence multiply(10) delete-next-word()
		    will delete 10 words.  It does not mat-
		    ter whether these actions take place in
		    one event or many events.  Using the
		    default translations the key sequence
		    Control-u, Control-d will delete 4 char-
		    acters.  Multiply actions can be
		    chained, thus multiply(5) multiply(5) is
		    the same as multiply(25).  If the string
		    reset is passed to the multiply action
		    the effects of all previous multiplies
		    are removed and a beep is sent to the
		    display.

form-paragraph()    This action removes all the Carriage
		    Returns from the current paragraph and
		    reinserts them so that each line is as



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		    long as possible, while still fitting on
		    the current screen.  Lines are broken at
		    word boundaries if at all possible.
		    This action currently works only on Text
		    widgets that use ASCII text.

transpose-characters()
		    This action will swap the position of
		    the character to the left of the insert
		    point with the character to the right of
		    the insert point.  The insert point will
		    then be advanced one character.

no-op([action])     The no-op action makes no change to the
		    text widget, and is mainly used to over-
		    ride translations.	This action takes
		    one optional argument.  If this argument
		    is RingBell then a beep is sent to the
		    display.

XawWMProtocols([wm_protocol_name])

		    This action is written specifically for
		    the file insertion and the search and
		    replace dialog boxes.  This action is
		    attached to those shells by the Text
		    widget, in order to handle ClientMessage
		    events with the WM_PROTOCOLS atom in the
		    detail field.  This action supports
		    WM_DELETE_WINDOW on the Text widget pop-
		    ups, and may support other window man-
		    ager protocols if necessary in the
		    future.  The popup will be dismissed if
		    the window manager sends a
		    WM_DELETE_WINDOW request and there are
		    no parameters in the action call, which
		    is the default.  The popup will also be
		    dismissed if the parameters include the
		    string ``wm_delete_window,'' and the
		    event is a ClientMessage event request-
		    ing dismissal or is not a ClientMessage
		    event.  This action is not sensitive to
		    the case of the strings passed as param-
		    eters.

reconnect-im()	    When the international resource is true,
		    input is usually passed to an input
		    method, a separate process, for compos-
		    ing.  Sometimes the connection to this
		    process gets severed; this action will
		    attempt to reconnect it.  Causes for
		    severage include network trouble, and
		    the user explicitly killing one input
		    method and starting a new one.  This



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		    action may also establish first connec-
		    tion when the application is started
		    before the input method.

5.2.7.	Text Selections for Application Programmers

The default behavior of the text selection array is
described in the section called Text Selections for Users.
To modify the selections a programmer must construct a Xaw-
TextSelectType array (called the selection array), contain-
ing the selections desired, and pass this as the new value
for the selectionTypes resource.  The selection array may
also be modified using the XawTextSetSelectionArray func-
tion.  All selection arrays must end with the value Xawse-
lectNull.  The selectionTypes resource has no converter reg-
istered and cannot be modified through the resource manager.

The array contains a list of entries that will be called
when the user attempts to select text in rapid succession
with the select-start action (usually by clicking a pointer
button).  The first entry in the selection array will be
used when the select-start action is initially called.	The
next entry will be used when select-start is called again,
and so on.  If a timeout value (1/10 of a second) is
exceeded, the the next select-start action will begin at the
top of the selection array.  When XawselectNull is reached
the array is recycled beginning with the first element.

XawselectAll   Selects the contents of the entire buffer.
Xawse-	       Selects text characters as the pointer
lectChar       moves over them.
Xawselect-     Selects the entire line.
Line
Xawselect-     Indicates the end of the selection array.
Null
Xawselect-     Selects the entire paragraph.
Paragraph
XawselectPo-   Selects the current pointer position.
sition
Xawselect-     Selects whole words as the pointer moves
Word	       onto them.


The default selectType array is:



{XawselectPosition, XawselectWord, XawselectLine, XawselectParagraph, XawselectAll, XawselectNull}



The selection array is not copied by the text widgets.	The
application must allocate space for the array and cannot
deallocate or change it until the text widget is destroyed



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or until a new selection array is set.

5.3.  Default Translation Bindings

The following translations are defaults built into every
Text widget.  They can be overridden, or replaced by speci-
fying a new value for the Text widget's translations
resource.



     Ctrl<Key>A:	 beginning-of-line() \n\
     Ctrl<Key>B:	 backward-character() \n\
     Ctrl<Key>D:	 delete-next-character() \n\
     Ctrl<Key>E:	 end-of-line() \n\
     Ctrl<Key>F:	 forward-character() \n\
     Ctrl<Key>G:	 multiply(Reset) \n\
     Ctrl<Key>H:	 delete-previous-character() \n\
     Ctrl<Key>J:	 newline-and-indent() \n\
     Ctrl<Key>K:	 kill-to-end-of-line() \n\
     Ctrl<Key>L:	 redraw-display() \n\
     Ctrl<Key>M:	 newline() \n\
     Ctrl<Key>N:	 next-line() \n\
     Ctrl<Key>O:	 newline-and-backup() \n\
     Ctrl<Key>P:	 previous-line() \n\
     Ctrl<Key>R:	 search(backward) \n\
     Ctrl<Key>S:	 search(forward) \n\
     Ctrl<Key>T:	 transpose-characters() \n\
     Ctrl<Key>U:	 multiply(4) \n\
     Ctrl<Key>V:	 next-page() \n\
     Ctrl<Key>W:	 kill-selection() \n\
     Ctrl<Key>Y:	 insert-selection(CUT_BUFFER1) \n\
     Ctrl<Key>Z:	 scroll-one-line-up() \n\
     Ctrl<Key>\:	 reconnect-im() \n\
     Meta<Key>B:	 backward-word() \n\
     Meta<Key>F:	 forward-word() \n\
     Meta<Key>I:	 insert-file() \n\
     Meta<Key>K:	 kill-to-end-of-paragraph() \n\
     Meta<Key>Q:	 form-paragraph() \n\
     Meta<Key>V:	 previous-page() \n\
     Meta<Key>Y:	 insert-selection(PRIMARY, CUT_BUFFER0) \n\
     Meta<Key>Z:	 scroll-one-line-down() \n\
     :Meta<Key>d:	 delete-next-word() \n\
     :Meta<Key>D:	 kill-word() \n\
     :Meta<Key>h:	 delete-previous-word() \n\
     :Meta<Key>H:	 backward-kill-word() \n\
     :Meta<Key>\<:	 beginning-of-file() \n\
     :Meta<Key>\>:	 end-of-file() \n\
     :Meta<Key>]:	 forward-paragraph() \n\
     :Meta<Key>[:	 backward-paragraph() \n\
     ~Shift Meta<Key>Delete:delete-previous-word() \n\
      Shift Meta<Key>Delete:backward-kill-word() \n\
     ~Shift Meta<Key>Backspace:delete-previous-word() \n\
      Shift Meta<Key>Backspace:backward-kill-word() \n\



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     <Key>Right:	 forward-character() \n\
     <Key>Left: 	 backward-character() \n\
     <Key>Down: 	 next-line() \n\
     <Key>Up:		 previous-line() \n\
     <Key>Delete:	 delete-previous-character() \n\
     <Key>BackSpace:	 delete-previous-character() \n\
     <Key>Linefeed:	 newline-and-indent() \n\
     <Key>Return:	 newline() \n\
     <Key>:		 insert-char() \n\
     <Key>Kanji:	 reconnect-im() \n\
     <FocusIn>: 	 focus-in() \n\
     <FocusOut>:	 focus-out() \n\
     <Btn1Down>:	 select-start() \n\
     <Btn1Motion>:	 extend-adjust() \n\
     <Btn1Up>:		 extend-end(PRIMARY, CUT_BUFFER0) \n\
     <Btn2Down>:	 insert-selection(PRIMARY, CUT_BUFFER0) \n\
     <Btn3Down>:	 extend-start() \n\
     <Btn3Motion>:	 extend-adjust() \n\
     <Btn3Up>:		 extend-end(PRIMARY, CUT_BUFFER0) \n


5.4.  Text Functions

The following functions are provided as convenience routines
for use with the Text widget.  Although many of these
actions can be performed by modifying resources, these
interfaces are frequently more efficient.

These data structures are defined in the Text widget's pub-
lic header file, <X11/Xaw/Text.h>.

typedef long XawTextPosition;


Character positions in the Text widget begin at 0 and end at
n, where n is the number of characters in the Text source
widget.


typedef struct {
     int firstPos;
     int length;
     char *ptr;
     unsigned long format;
} XawTextBlock, *XawTextBlockPtr;



firstPos  The first position, or index, to use within the
	  ptr field.  The value is commonly zero.

length	  The number of characters to be used from the ptr
	  field.  The number of characters used is commonly
	  the number of characters in ptr, and must not be



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	  greater than the length of the string in ptr.

ptr	  Contains the string to be referenced by the Text
	  widget.

format	  This flag indicates whether the data pointed to by
	  ptr is char or wchar_t.  When the associated wid-
	  get has international set to false this field must
	  be XawFmt8Bit.  When the associated widget has
	  international set to true this field must be
	  either XawFmt8Bit or XawFmtWide.

Note: Previous versions of Xaw used FMT8BIT, which has been
retained for backwards compatibility. FMT8BIT is deprecated
and will eventually be removed from the implementation.

5.4.1.	Selecting Text

To select a piece of text, use XawTextSetSelection:

void XawTextSetSelection(w, left, right)
     Widget w;
     XawTextPosition left, right;


w	  Specifies the Text widget.

left	  Specifies the character position at which the
	  selection begins.

right	  Specifies the character position at which the
	  selection ends.

See section 5.4 for a description of XawTextPosition.  If
redisplay is enabled, this function highlights the text and
makes it the PRIMARY selection.  This function does not have
any effect on CUT_BUFFER0.


5.4.2.	Unhighlighting Text

To unhighlight previously highlighted text in a widget, use
XawTextUnsetSelection:

void XawTextUnsetSelection(w)
     Widget w;


w	  Specifies the Text widget.

5.4.3.	Getting Current Text Selection

To retrieve the text that has been selected by this text
widget use XawTextGetSelectionPos:



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void XawTextGetSelectionPos(w, begin_return, end_return)
     Widget w;
     XawTextPosition *begin_return, *end_return;


w	  Specifies the Text widget.

begin_return
	  Returns the beginning of the text selection.

end_return
	  Returns the end of the text selection.

See section 5.4 for a description of XawTextPosition.  If
the returned values are equal, no text is currently
selected.

5.4.4.	Replacing Text

To modify the text in an editable Text widget use XawTextRe-
place:

int XawTextReplace(w, start, end, text)
     Widget w;
     XawTextPosition start, end;
     XawTextBlock *text;


w	  Specifies the Text widget.

start	  Specifies the starting character position of the
	  text replacement.

end	  Specifies the ending character position of the
	  text replacement.

text	  Specifies the text to be inserted into the file.

This function will not be able to replace text in read-only
text widgets.  It will also only be able to append text to
an append-only text widget.

See section 5.4 for a description of XawTextPosition and
XawTextBlock.

This function may return the following values:

XawEditDone The text replacement was successful.

XawPositionError
	    The edit mode is XawtextAppend and start is not
	    the position of the last character of the
	    source.




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XawEditError
	    Either the Source was read-only or the range to
	    be deleted is larger than the length of the
	    Source.


The XawTextReplace arguments start and end represent the
text source character positions for the existing text that
is to be replaced by the text in the text block.  The char-
acters from start up to but not including end are deleted,
and the characters specified on the text block are inserted
in their place.  If start and end are equal, no text is
deleted and the new text is inserted after start.

5.4.5.	Searching for Text

To search for a string in the Text widget, use Xaw-
TextSearch:

XawTextPosition XawTextSearch(w, dir, text)
      Widget w;
      XawTextScanDirection dir;
      XawTextBlock * text;


w	  Specifies the Text widget.

dir	  Specifies the direction to search in.  Legal val-
	  ues are XawsdLeft and XawsdRight.

text	  Specifies a text block structure that contains the
	  text to search for.

See section 5.4 for a description of XawTextPosition and
XawTextBlock.  The XawTextSearch function will begin at the
insertion point and search in the direction specified for a
string that matches the one passed in text.  If the string
is found the location of the first character in the string
is returned.  If the string could not be found then the
value XawTextSearchError is returned.

5.4.6.	Redisplaying Text

To redisplay a range of characters, use XawTextInvalidate:

void XawTextInvalidate(w, from, to)
      Widget w;
      XawTextPosition from, to;


w	  Specifies the Text widget.

from	  Specifies the start of the text to redisplay.




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to	  Specifies the end of the text to redisplay.

See section 5.4 for a description of XawTextPosition.  The
XawTextInvalidate function causes the specified range of
characters to be redisplayed immediately if redisplay is
enabled or the next time that redisplay is enabled.


To enable redisplay, use XawTextEnableRedisplay:

void XawTextEnableRedisplay(w)
      Widget w;


w	  Specifies the Text widget.

The XawTextEnableRedisplay function flushes any changes due
to batched updates when XawTextDisableRedisplay was called
and allows future changes to be reflected immediately.


To disable redisplay while making several changes, use Xaw-
TextDisableRedisplay.

void XawTextDisableRedisplay(w)
       Widget w;


w	  Specifies the Text widget.

The XawTextDisableRedisplay function causes all changes to
be batched until either XawTextDisplay or XawTextEnableRe-
display is called.


To display batched updates, use XawTextDisplay:

void XawTextDisplay(w)
     Widget w;


w	  Specifies the Text widget.

The XawTextDisplay function forces any accumulated updates
to be displayed.

5.4.7.	Resources Convenience Routines

To obtain the character position of the left-most character
on the first line displayed in the widget (the value of the
displayPosition resource), use XawTextTopPosition.






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XawTextPosition XawTextTopPosition(w)
      Widget w;


w	  Specifies the Text widget.


To assign a new selection array to a text widget use Xaw-
TextSetSelectionArray:

void XawTextSetSelectionArray(w, sarray)
      Widget w;
      XawTextSelectType * sarray;


w	  Specifies the Text widget.

sarray	  Specifies a selection array as defined in the sec-
	  tion called Text Selections for Application Pro-
	  grammers.

Calling this function is equivalent to setting the value of
the selectionTypes resource.


To move the insertion point to the specified source posi-
tion, use XawTextSetInsertionPoint:

void XawTextSetInsertionPoint(w, position)
      Widget w;
      XawTextPosition position;


w	  Specifies the Text widget.

position  Specifies the new position for the insertion
	  point.

See section 5.4 for a description of XawTextPosition.  The
text will be scrolled vertically if necessary to make the
line containing the insertion point visible.  Calling this
function is equivalent to setting the insertPosition
resource.


To obtain the current position of the insertion point, use
XawTextGetInsertionPoint:

XawTextPosition XawTextGetInsertionPoint(w)
      Widget w;


w	  Specifies the Text widget.




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See section 5.4 for a description of XawTextPosition.  The
result is equivalent to retrieving the value of the insert-
Position resource.


To replace the text source in the specified widget, use Xaw-
TextSetSource:

void XawTextSetSource(w, source, position)
      Widget w;
      Widget source;
      XawTextPosition position;


w	  Specifies the Text widget.

source	  Specifies the text source object.

position  Specifies character position that will become the
	  upper left hand corner of the displayed text.
	  This is usually set to zero.

See section 5.4 for a description of XawTextPosition.  A
display update will be performed if redisplay is enabled.


To obtain the current text source for the specified widget,
use XawTextGetSource:

Widget XawTextGetSource(w)
      Widget w;


w	  Specifies the Text widget.

This function returns the text source that this Text widget
is currently using.


To enable and disable the insertion point, use XawTextDis-
playCaret:

void XawTextDisplayCaret(w, visible)
      Widget w;
      Boolean visible;


w	  Specifies the Text widget.

visible   Specifies whether or not the caret should be dis-
	  played.

If visible is False the insertion point will be disabled.
The marker is re-enabled either by setting visible to True,



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by calling XtSetValues, or by executing the display-caret
action routine.

5.5.  Ascii Text Widget



Application Header file<X11/Xaw/AsciiText.h>
ClassHeader file    <X11/Xaw/AsciiTextP.h>
Class		    asciiTextWidgetClass
Class Name	    Text
Superclass	    Text
Sink Name	    textSink
Source Name	    textSource



For the ease of internationalization, the AsciiText widget
class name has not been changed, although it is actually
able support non-ASCII locales.  The AsciiText widget is
really a collection of smaller parts.  It includes the Text
widget itself, a ``Source'' (which supports memory manage-
ment), and a ``Sink'' (which handles the display).  There
are currently two supported sources, the AsciiSrc and Multi-
Src, and two supported sinks, the AsciiSink and MultiSink.
Some of the resources listed below are not actually
resources of the AsciiText, but belong to the associated
source or sink.  This is is noted in the explanation of each
resource where it applies.  When specifying these resources
in a resource file it is necessary to use *Asci-
iText*resource_name instead of *AsciiText.resource_name,
since they actually belong to the children of the AsciiText
widget, and not the AsciiText widget itself.  However, these
resources may be set directly on the AsciiText widget at
widget creation time, or via XtSetValues.

5.5.1.	Resources

When creating an AsciiText widget instance, the following
resources are retrieved from the argument list or from the
resource database:


------------------------------------------------------------------------------------
Name		      Class	       Type		 NotesDefault Value
------------------------------------------------------------------------------------
accelerators	      Accelerators     AcceleratorTable       NULL
ancestorSensitive     AncestorSensitiveBoolean		 D    True
autoFill	      AutoFill	       Boolean		      False
background	      Background       Pixel		      XtDefaultBackground
backgroundPixmap      Pixmap	       Pixmap		      XtUnspecifiedPixmap
borderColor	      BorderColor      Pixel		      XtDefaultForeground
borderPixmap	      Pixmap	       Pixmap		      XtUnspecifiedPixmap




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------------------------------------------------------------------------------------
Name		      Class	       Type		 NotesDefault Value
------------------------------------------------------------------------------------
borderWidth	      BorderWidth      Dimension	      1
bottomMargin	      Margin	       Position 	      2
callback	      Callback	       XtCallbackList	      NULL
colormap	      Colormap	       Colormap 	      Parent's Colormap
cursor		      Cursor	       Cursor		      XC_xterm
cursorName	      Cursor	       String		      NULL
dataCompression       DataCompression  Boolean		      True
depth		      Depth	       int		 C    Parent's Depth
destroyCallback       Callback	       XtCallbackList	      NULL
displayCaret	      Output	       Boolean		      True
displayNonprinting    Output	       Boolean		      True
displayPosition       TextPosition     XawTextPosition	      0
echo		      Output	       Boolean		      True
editType	      EditType	       XawTextEditType	      XawtextRead
font		      Font	       XFontStruct*	      XtDefaultFont
fontSet 	      FontSet	       XFontSet 	      XtDefaultFontSet
foreground	      Foreground       Pixel		      XtDefaultForeground
height		      Height	       Dimension	 A    Font height + margins
insensitiveBorder     Insensitive      Pixmap		      GreyPixmap
insertPosition	      TextPosition     int		      0
international	      International    Boolean		 C    False
leftMargin	      Margin	       Dimension	      2
length		      Length	       int		 A    length of string
mappedWhenManaged     MappedWhenManagedBoolean		      True
pieceSize	      PieceSize        XawTextPosition	      BUFSIZ
pointerColor	      Foreground       Pixel		      XtDefaultForeground
pointerColorBackgroundBackground       Pixel		      XtDefaultBackground
resize		      Resize	       XawTextResizeMode      XawtextResizeNever
rightMargin	      Margin	       Position 	      2
screen		      Screen	       Screen		 R    Parent's Screen
scrollHorizontal      Scroll	       XawTextScrollMode      XawtextScrollNever
scrollVertical	      Scroll	       XawTextScrollMode      XawtextScrollNever
selectTypes	      SelectTypes      XawTextSelectType*     See above
sensitive	      Sensitive        Boolean		      True
string		      String	       String		      NULL
textSink	      TextSink	       Widget		      An AsciiSink
textSource	      TextSource       Widget		      An AsciiSrc
topMargin	      Margin	       Position 	      2
translations	      Translations     TranslationTable       See above
type		      Type	       XawAsciiType	      XawAsciiString
useStringInPlace      UseStringInPlace Boolean		      False
width		      Width	       Dimension	      100
wrap		      Wrap	       WrapMode 	      XawtextWrapNever
x		      Position	       Position 	      0
y		      Position	       Position 	      0
------------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X



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	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

autoFill       If this resource is True the text widget will
	       automatically break a line when the user
	       attempts to type into the right margin.	The
	       attribute has no effect on files or text
	       inserted into the text widget.  It only
	       checks to see if the action should be taken
	       when a user enters a new character via the
	       insert-character action.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

bottomMargin
leftMargin
rightMargin
topMargin      The amount of space, in pixels, between the
	       edge of the window and the corresponding edge
	       of the text within the window.  If there is a
	       scrollbar active on this edge, then this is
	       the space between the text and the scrollbar.

callback       The callbacks registered on this resource
	       will be called every time the text buffer
	       changes, after the text has been updated.



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	       This is a resource of the associated source.

colormap       The colormap that this widget will use.

cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.

cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will over-
	       ride the cursor resource if both are speci-
	       fied. (See 2.4.1)

dataCompression
	       The AsciiSrc uses an algorithm that may cause
	       the text buffer to grow to about twice the
	       size of the actual text over time, as the
	       text is edited.	On systems where CPU cycles
	       are cheaper than memory, it is helpful to
	       spend some extra time to compress this buffer
	       back to its minimum size.  If this resource
	       is True, the AsciiSrc will compress its data
	       to the minimum size required every time the
	       text string is saved, or the value of the
	       string is queried.  This is a resource of the
	       associated source.

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

displayCaret   Whether or not to display the text insert
	       point.

displayNonprinting
	       If this resource is True, the Text widget
	       will display all non-printable characters as
	       the string ^@.  If False, the Text widget
	       will just leave a blank space where a non-
	       printable character exists in the text
	       buffer.	This is a resource of the associated
	       sink.

displayPosition
	       The position in the text buffer of the char-
	       acter that is currently displayed in the
	       upper left hand corner of the text display.

editType       This is the type of editing that will be
	       allowed in this text widget.  Legal values
	       are XawtextRead, XawtextEdit, and



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	       XawtextAppend.  A converter is registered for
	       this resource that will convert the following
	       strings: read, edit, and append.  This is a
	       resource of the associated source.

echo	       Whether or not to echo characters to the
	       screen.	The buffer can still be edited, but
	       nothing is displayed.  This mode can be use-
	       ful for entering passwords and other sensi-
	       tive information.  This is a resource of the
	       associated sink.

font	       The text font to use when displaying the
	       string, when the international resource is
	       false.  This is a resource of the associated
	       sink.

font	       The text font set to use when displaying the
	       string, when the international resource is
	       true.  This is a resource of the associated
	       sink.

foreground     A pixel value which indexes the Text widget's
	       colormap to derive the foreground color used
	       by the text sink.  This is a resource of the
	       associated sink.

height
width	       The height and width of this widget in pix-
	       els.

insensitiveBorder
	       This pixmap will be tiled into the widget's
	       border if the widget becomes insensitive.

insertPosition This is the location of the insert point.  It
	       is expressed in characters from the beginning
	       of the file.  The cursor will always be
	       forced to be on the screen.  This resource
	       may therefore be used to scroll the text dis-
	       play to a certain character position.

length	       If the useStringInPlace resource is False
	       this attribute has no effect.  If that
	       resource is True, however, then the length
	       resource specifies the length of the buffer
	       passed to the text widget in the string
	       resource.  This is a resource of the associ-
	       ated source.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.



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pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.

pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

pieceSize      This is the size of the internal chunks into
	       which the text buffer is broken down for mem-
	       ory management.	The larger this value the
	       less segmented your memory will be, but the
	       slower your editing will be.  The text wid-
	       gets will always allocate a chunk of memory
	       this size to stuff the string into, so when
	       using small strings, having this buffer large
	       can waste memory.  This resource has no
	       effect if useStringInPlace is True.  This is
	       a resource of the associated source.

resize	       Controls whether or not the Text widget
	       attempts to resize itself when it is no
	       longer able to display the full text buffer
	       in the associated window.  Any attempt by the
	       Text widget to resize itself is always sub-
	       ject to the constraints imposed by its par-
	       ent.  The values XawtextResizeNever, Xawtex-
	       tResizeWidth, XawtextResizeHeight, and Xaw-
	       textResizeBoth are all acceptable for this
	       resource.  A converter is registered for this
	       resource that will convert the following
	       strings: never, height, width, and both.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

scrollHorizontal
scrollVertical These resources control the placement of
	       scrollbars on the left and bottom edge of the
	       text widget.  These resources accept the val-
	       ues XawtextScrollAlways, XawtextScrollWhen-
	       Needed, and XawtextScrollNever.	A converter
	       is registered for this resource that will
	       convert the following strings: always, never,
	       and whenNeeded.	If XawtextScrollWhenNeeded
	       is specified, the appropriate scrollbar will
	       only appear when there is text in the buffer
	       that is not able to fit within the bounds of
	       the current window.  The scrollbar will dis-
	       appear when the text once again fits within
	       the window.



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selectTypes    Specifies the selection type array that is
	       used when multi-click is activated (see Text
	       Selections for Application Programmers for
	       details).  This resource is used in place,
	       and must not be freed until the widget is
	       destroyed.  There is no type converter regis-
	       tered for this resource, so it may not be set
	       from the resource manager.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

string	       If type is XawAsciiString then this string
	       contains the buffer to be displayed in the
	       widget.	If type is XawAsciiFile then the
	       string contains the name of the file to be
	       displayed.  This string is normally copied by
	       the text widget into internal memory, but may
	       be used in place by setting the useStringIn-
	       Place resource.	As of X11R4 this is a set-
	       table resource.	This is a resource of the
	       associated source.  When the string resource
	       is queried, using XtGetValues, and useString-
	       InPlace is false, the value returned is valid
	       until the next time the string resource is
	       queried, or until the application writer
	       calls XawAsciiSrcFreeString.  If useStringIn-
	       Place is true, a pointer to the actual string
	       is returned.  See also section 5.6.

textSink
textSource     These are the TextSink or TextSource objects
	       used by this widget.  When international is
	       set to true the AsciiText widget initializes
	       these resources to point to an MultiSink and
	       MultiSrc respectively.  When international is
	       set to false the AsciiText widget initializes
	       these resources to point to an AsciiSink and
	       AsciiSrc respectively.

translations   The event bindings associated with this wid-
	       get.

type	       This resource may be either XawAsciiString or
	       XawAsciiFile.  The value of this resource
	       determines whether the string resource con-
	       tains the name of a file to be opened or a
	       buffer to be displayed by the text widget.  A
	       converter has been registered for this
	       resource and accepts the values string and
	       file.  This is a resource of the associated
	       source.



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useStringInPlace
	       Setting this resource to True will disable
	       the memory management provided by the Text
	       widget, updating the string resource in
	       place.  Using the string in place can be much
	       more efficient for text widgets that display
	       static data, or where the programmer wishes
	       to impose strict constraints on the contents
	       of the string.  When using the string in
	       place be sure that: the length of the string
	       is specified by setting the length resource,
	       the type of the Text widget is XawAsci-
	       iString, and that the string exists for the
	       lifetime of the text widget, or until it has
	       been reset.  Note: Since the MultiSrc and
	       AsciiSrc have different data formats, use of
	       this resource forces application code to be
	       cognisant as to which of the two is being
	       used.  Application programming is simplified
	       when use of this resource is avoided.  This
	       is a resource of the associated source.

wrap	       When the text in any one line is wider than
	       the window there are several possible
	       actions.  This resource allows the user to
	       decide what will happen.  The accepted values
	       for this resource are XawtextWrapNever, Xaw-
	       textWrapLine, and XawtextWrapWord.  With Xaw-
	       textWrapLine all text that is beyond the
	       right edge of the window will be displayed on
	       the next line.  With XawtextWrapWord the same
	       action occurs but the text is broken at a
	       word boundary if possible.  If no wrapping is
	       enabled then the text will extend off the
	       edge of the window, and a small rectangle
	       will be painted in the right margin to alert
	       the user that this line is too long.  A con-
	       verter is registered for this resource that
	       will convert the following strings: never,
	       word, and line.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.



5.6.  Ascii Source Object and Multi Source Object



Application Header file<X11/Xaw/AsciiSrc.h> or <X11/Xaw/MultiSrc.h>
Class Header file   <X11/Xaw/AsciiSrcP.h> or  <X11/Xaw/MultiSrcP.h>
Class		    asciiSrcObjectClass or multiSrcObjectClass



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Class Name	    AsciiSrc or MultiSrc
Superclass	    TextSource


The AsciiSrc or MultiSrc object is used by a text widget to
read the text from a file or string in memory.	Depending on
its international resource, an AsciiText widget will create
one or the other of these when the AsciiText itself is cre-
ated.  Both types are nearly identical; the following dis-
cussion applies to both, with MultiSrc differences noted
only as they occur.

The AsciiSrc understands all Latin1 characters plus Tab and
Carriage Return.  The MultiSrc understands any set of char-
acter sets that the underlying X implementation's interna-
tionalization handles.

The AsciiSrc can be either of two types: XawAsciiFile or
XawAsciiString.

AsciiSrc objects of type XawAsciiFile read the text from a
file and store it into an internal buffer.  This buffer may
then be modified, provided the text widget is in the correct
edit mode, just as if it were a source of type XawAsci-
iString.  Unlike R3 and earlier versions of the AsciiSrc, it
is now possible to specify an editable disk source.  The
file is not updated, however, until a call to XawAsciiSave
is made.  When the source is in this mode the useStringIn-
Place resource is ignored.

AsciiSrc objects of type XawAsciiString have the text buffer
implemented as a string.  MultiSrc objects of type XawAsci-
iString have the text buffer implemented as a wide character
string.  The string owner is responsible for allocating and
managing storage for the string.

In the default case for AsciiSrc objects of type XawAsci-
iString, the resource useStringInPlace is false, and the
widget owns the string.  The initial value of the string
resource, and any update made by the application programmer
to the string resource with XtSetValues, is copied into mem-
ory private to the widget, and managed internally by the
widget.  The application writer does not need to worry about
running out of buffer space (subject to the total memory
available to the application).	The performance does not
decay linearly as the buffer grows large, as is necessarily
the case when the text buffer is used in place.   The appli-
cation writer must use XtGetValues to determine the contents
of the text buffer, which will return a copy of the widget's
text buffer as it existed at the time of the XtGetValues
call.	This copy is not affected by subsequent updates to
the text buffer, i.e., it is not updated as the user types
input into the text buffer.  This copy is freed upon the
next call to XtGetValues to retrieve the string resource;



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however, to conserve memory, there is a convenience routine,
XawAsciiSrcFreeString, allowing the application programmer
to direct the widget to free the copy.

When the resource useStringInPlace is true and the AsciiSrc
object is of type XawAsciiString, the application is the
string owner.  The widget will take the value of the string
resource as its own text buffer, and the length resource
indicates the buffer size.   In this case the buffer con-
tents change as the user types at the widget; it is not nec-
essary to call XtGetValues on the string resource to deter-
mine the contents of the buffer--it will simply return the
address of the application's implementation of the text
buffer.

5.6.1.	Resources

When creating an AsciiSrc object instance, the following
resources are retrieved from the argument list or from the
resource database:


------------------------------------------------------------------------------------
Name		   Class	      Type	       Notes   Default Value
------------------------------------------------------------------------------------
callback	   Callback	      XtCallbackList	       NULL
dataCompression    DataCompression    Boolean		       True
destroyCallback    Callback	      Callback		       NULL
editType	   EditType	      EditMode		       XawtextRead
length		   Length	      Int	       A       length of string
pieceSize	   PieceSize	      Int		       BUFSIZ
string		   String	      String		       NULL
type		   Type 	      AsciiType 	       XawAsciiString
useStringInPlace   UseStringInPlace   Boolean		       False
------------------------------------------------------------------------------------


callback       The callbacks registered on this resource
	       will be called every time the text buffer
	       changes, after the text has been updated.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

dataCompression
	       The AsciiSrc uses an algorithm that may cause
	       the text buffer to grow to about twice the
	       size of the actual text over time, as the
	       text is edited.	On systems where CPU cycles
	       are cheaper than memory, it is helpful to
	       spend some extra time to compress this buffer
	       back to its minimum size.  If this resource
	       is True, the AsciiSrc will compress its data



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	       to the minimum size required every time the
	       text string is saved, or the value of the
	       string is queried.

editType       This is the type of editing that will be
	       allowed in this text widget.  Legal values
	       are XawtextRead, XawtextEdit, and XawtextAp-
	       pend.  A converter is registered for this
	       resource that will convert the following
	       strings: read, edit, and append.

length	       If the useStringInPlace resource is False
	       this attribute has no effect.  If that
	       resource is True, however, then the length
	       resource specifies the length of the buffer
	       passed to the text widget in the string
	       resource.

pieceSize      This is the size of the internal chunks into
	       which the text buffer is broken down for mem-
	       ory management.	The larger this value the
	       less segmented your memory will be, but the
	       slower your editing will be.  The text wid-
	       gets will always allocate a chunk of memory
	       this size to stuff the string into, so when
	       using small strings, having this buffer large
	       can waste memory.  This resource has no
	       effect if useStringInPlace is True.

string	       If type is XawAsciiString then this string
	       contains the buffer to be displayed in the
	       widget.	If type is XawAsciiFile then the
	       string contains the name of the file to be
	       displayed.  This string is normally copied by
	       the text widget into internal memory, but may
	       be used in place by setting the useStringIn-
	       Place resource.	As of X11R4 this is a set-
	       table resource.	When the string resource is
	       queried, using XtGetValues, and useStringIn-
	       Place is false, the value returned is valid
	       until the next time the string resource is
	       queried, or until the application writer
	       calls XawAsciiSrcFreeString.  If useStringIn-
	       Place is true, a pointer to the actual string
	       is returned.  See also section 5.6.

type	       This resource may be either XawAsciiString or
	       XawAsciiFile.  The value of this resource
	       determines whether the string resource con-
	       tains the name of a file to be opened or a
	       buffer to be displayed by the text widget.  A
	       converter has been registered for this
	       resource and accepts the values string and
	       file.



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useStringInPlace
	       Setting this resource to True will disable
	       the memory management provided by the Text
	       widget, updating the string resource in
	       place.  Using the string in place can be much
	       more efficient for text widgets that display
	       static data, or where the programmer wishes
	       to impose strict constraints on the contents
	       of the string.  When using the string in
	       place be sure that: the length of the string
	       is specified by setting the length resource,
	       the type of the Text widget is XawAsci-
	       iString, and that the string exists for the
	       lifetime of the text widget, or until it has
	       been reset.  Note: Since the MultiSrc and
	       AsciiSrc have different data formats, use of
	       this resource forces application code to be
	       cognisant as to which of the two is being
	       used.  Application programming is simplified
	       when use of this resource is avoided.

5.6.2.	Convenience Routines

The AsciiSrc has a few convenience routines that allow the
application programmer quicker or easier access to some of
the commonly used functionality of the AsciiSrc.

5.6.2.1.  Conserving Memory

When the AsciiSrc widget is not in useStringInPlace mode
space must be allocated whenever the file is saved, or the
string is requested with a call to XtGetValues.  This memory
is allocated on the fly, and remains valid until the next
time a string needs to be allocated.  You may save memory by
freeing this string as soon as you are done with it by call-
ing XawAsciiSrcFreeString.

void XawAsciiSourceFreeString(w)
Widget w;


w	  Specifies the AsciiSrc object.

This function will free the memory that contains the string
pointer returned by XtGetValues.  This will normally happen
automatically when the next call to XtGetValues occurs, or
when the widget is destroyed.

5.6.2.2.  Saving Files

To save the changes made in the current text source into a
file use XawAsciiSave.





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Boolean XawAsciiSave(w)
Widget w;


w	  Specifies the AsciiSrc object.

XawAsciiSave returns True if the save was successful.  It
will update the file named in the string resource.  If the
buffer has not been changed, no action will be taken.  This
function only works on an AsciiSrc of type XawAsciiFile.


To save the contents of the current text buffer into a named
file use XawAsciiSaveAsFile.

Boolean XawAsciiSaveAsFile(w, name)
Widget w;
String name;


w	  Specifies the AsciiSrc object.

name	  The name of the file to save the current buffer
	  into.

This function returns True if the save was successful.
XawAsciiSaveAsFile will work with a buffer of either type
XawAsciiString or type XawAsciiFile.

5.6.2.3.  Seeing if the Source has Changed

To find out if the text buffer in an AsciiSrc object has
changed since the last time it was saved with XawAsciiSave
or queried use XawAsciiSourceChanged.

Boolean XawAsciiSourceChanged(w)
Widget w;


w	  Specifies the AsciiSrc object.

This function will return True if the source has changed
since the last time it was saved or queried.  The internal
change flag is reset whenever the string is queried via
XtGetValues or the buffer is saved via XawAsciiSave.


5.7.  Ascii Sink Object and Multi Sink Object



Application Header file<X11/Xaw/AsciiSink.h>
Class Header file   <X11/Xaw/AsciiSinkP.h>
Class		    asciiSinkObjectClass



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Class Name	    AsciiSink
Superclass	    TextSink


The AsciiSink or MultiSink object is used by a text widget
to render the text.  Depending on its international
resource, a AsciiText widget will create one or the other of
these when the AsciiText itself is created.  Both types are
nearly identical; the following discussion applies to both,
with MultiSink differences noted only as they occur.  The
AsciiSink will display all printing characters in an 8 bit
font, along with handling Tab and Carriage Return.  The name
has been left as ``AsciiSink'' for compatibility.  The Mul-
tiSink will display all printing characters in a font set,
along with handling Tab and Carriage Return.	The source
object also reports the text window metrics to the text wid-
gets.

5.7.1.	Resources

When creating an AsciiSink object instance, the following
resources are retrieved from the argument list or from the
resource database:


--------------------------------------------------------------------------------
Name		     Class	  Type		   Notes   Default Value
--------------------------------------------------------------------------------
background	     Background   Pixel 		   XtDefaultBackground
destroyCallback      Callback	  XtCallbackList	   NULL
displayNonprinting   Output	  Boolean		   True
echo		     Output	  Boolean		   True
font		     Font	  XFontStruct*		   XtDefaultFont
fontSet 	     FontSet	  XFontSet		   XtDefaultFontSet
foreground	     Foreground   Pixel 		   XtDefaultForeground
--------------------------------------------------------------------------------


background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.  This resource is retrieved
	       by the AsciiSink instead of being copied from
	       the Text widget.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

displayNonprinting
	       If this resource is True, the Text widget
	       will display all non-printable characters as
	       the string ^@.  If False, the Text widget
	       will just leave a blank space where a non-
	       printable character exists in the text



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	       buffer.

echo	       Whether or not to echo characters to the
	       screen.	The buffer can still be edited, but
	       nothing is displayed.  This mode can be use-
	       ful for entering passwords and other sensi-
	       tive information.

font	       The text font to use when displaying the
	       string.	(This resource is present in the
	       AsciiSink, but not the MultiSink.)

fontSet        The text font set to use when displaying the
	       string.	(This resource is present in the
	       MultiSink, but not the AsciiSink.)


5.8.  Customizing the Text Widget


The remainder of this chapter will describe customizing the
Text widget.  The Text widget may be customized by subclass-
ing, or by creating new sources and sinks.  Subclassing is
described in detail in Chapter 7; this section will describe
only those things that are specific to the Text widget.
Attributes of the Text widget base class and creating new
sources and sinks will be discussed.

The Text widget is made up of a number of different pieces,
with the Text widget as the base widget class.	It and the
AsciiText widget are the only true "widgets" in the Text
widget family.	The other pieces (sources and sinks) are X
Toolkit objects and have no window associated with them.  No
source or sink is useful unless assigned to a Text widget.

Each of the following pieces of the Text widget has a spe-
cific purpose, and will be, or has been, discussed in detail
in this chapter:

Text	       This is the glue that binds everything else
	       together.  This widget reads the text data
	       from the source, and displays the information
	       in the sink.  All translations and actions
	       are handled in the Text widget itself.

TextSink       This object is responsible for displaying and
	       clearing the drawing area.  It also reports
	       the configuration of the window that contains
	       the drawing area.  The TextSink does not have
	       its own window; instead it does its drawing
	       on the Text widget's window.

TextSrc        This object is responsible for reading, edit-
	       ing and searching through the text buffer.



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AsciiSink      This object is a subclass of the TextSink and
	       knows how to display ASCII text.  Support has
	       been added to display any 8-bit character
	       set, given the font.

MultiSink      This object is a subclass of the TextSink and
	       knows how to display font sets.

AsciiSrc       This object is a subclass of the TextSrc and
	       knows how to read strings and files.

MultiSrc       This object is a subclass of the TextSrc and
	       knows how to read strings and multibyte
	       files, converting them to wide characters
	       based on locale.

AsciiText      This widget is a subclass of the Text widget.
	       When created, the AsciiText automatically
	       creates and attaches either an AsciiSrc and
	       AsciiSink, or a MultiSrc and MultiSink, to
	       itself.	The AsciiText provides the simplest
	       interface to the Athena Text widgets.


5.9.  Text Widget



Application Header file<X11/Xaw/Text.h>
Class Header file   <X11/Xaw/TextP.h>
Class		    textWidgetClass
Class Name	    Text
Superclass	    Simple



The Text widget is the glue that binds all the other pieces
together, it maintains the internal state of the displayed
text, and acts as a mediator between the source and sink.

This section lists the resources that are actually part of
the Text widget, and explains the functionality provided by
each.

5.9.1.	Resources

When creating an Text widget instance, the following
resources are retrieved from the argument list or from the
resource database:








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------------------------------------------------------------------------------------
Name		      Class	       Type		 NotesDefault Value
------------------------------------------------------------------------------------
accelerators	      Accelerators     AcceleratorTable       NULL
ancestorSensitive     AncestorSensitiveBoolean		 D    True
autoFill	      AutoFill	       Boolean		      False
background	      Background       Pixel		      XtDefaultBackground
backgroundPixmap      Pixmap	       Pixmap		      XtUnspecifiedPixmap
borderColor	      BorderColor      Pixel		      XtDefaultForeground
borderPixmap	      Pixmap	       Pixmap		      XtUnspecifiedPixmap
borderWidth	      BorderWidth      Dimension	      1
bottomMargin	      Margin	       Position 	      2
colormap	      Colormap	       Colormap 	      Parent's Colormap
cursor		      Cursor	       Cursor		      XC_xterm
cursorName	      Cursor	       String		      NULL
depth		      Depth	       int		 C    Parent's Depth
destroyCallback       Callback	       XtCallbackList	      NULL
displayCaret	      Output	       Boolean		      True
displayPosition       TextPosition     XawTextPosition	      0
height		      Height	       Dimension	 A    Font height + margins
insensitiveBorder     Insensitive      Pixmap		      GreyPixmap
insertPosition	      TextPosition     int		      0
leftMargin	      Margin	       Position 	      2
mappedWhenManaged     MappedWhenManagedBoolean		      True
pointerColor	      Foreground       Pixel		      XtDefaultForeground
pointerColorBackgroundBackground       Pixel		      XtDefaultBackground
resize		      Resize	       XawTextResizeMode      XawtextResizeNever
rightMargin	      Margin	       Position 	      4
screen		      Screen	       Pointer		 R    Parent's Screen
scrollHorizontal      Scroll	       ScrollMode	      XawtextScrollNever
scrollVertical	      Scroll	       XawTextScrollMode      XawtextScrollNever
selectTypes	      SelectTypes      XawTextSelectType*     See above
sensitive	      Sensitive        Boolean		      True
textSink	      TextSink	       Widget		      NULL
textSource	      TextSource       Widget		      NULL
topMargin	      Margin	       Position 	      2
translations	      Translations     TranslationTable       See above
unrealizeCallback     Callback	       XtCallbackList	      NULL
width		      Width	       Dimension	      100
wrap		      Wrap	       WrapMode 	      XawtextWrapNever
x		      Position	       Position 	      0
y		      Position	       Position 	      0
------------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if



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	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

autoFill       If this resource is True the text widget will
	       automatically break a line when the user
	       attempts to type into the right margin.	The
	       attribute has no effect on files or text
	       inserted into the text widget.  It only
	       checks to see if the action should be taken
	       when a user enters a new character via the
	       insert-character action.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

bottomMargin
leftMargin
rightMargin
topMargin      The amount of space, in pixels, between the
	       edge of the window and the corresponding edge
	       of the text within the window.  If there is a
	       scrollbar active on this edge, then this is
	       the space between the text and the scrollbar.

colormap       The colormap that this widget will use.

cursor	       The image that will be displayed as the
	       pointer cursor whenever it is in this widget.
	       The use of this resource is deprecated in
	       favor of cursorName.

cursorName     The name of the symbol to use to represent
	       the pointer cursor.  This resource will



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	       override the cursor resource if both are
	       specified. (See 2.4.1)

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

displayCaret   Whether or not to display the text insert
	       point.

displayPosition
	       The position in the text buffer of the char-
	       acter that is currently displayed in the
	       upper left hand corner of the text display.

height
width	       The height and width of this widget in pix-
	       els.

insensitiveBorder
	       This pixmap will be tiled into the widget's
	       border if the widget becomes insensitive.

insertPosition This is the location of the insert point.  It
	       is expressed in characters from the beginning
	       of the file.  The cursor will always be
	       forced to be on the screen.  This resource
	       may therefore be used to scroll the text dis-
	       play to a certain character position.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

pointerColor   A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       pointer symbol specified by the cursorName
	       resource.

pointerColorBackground
		 A pixel value which indexes the widget's
		 colormap to derive the background color of
		 the pointer symbol specified by the cursor-
		 Name resource.

resize	       Controls whether or not the Text widget
	       attempts to resize itself when it is no
	       longer able to display the full text buffer
	       in the associated window.  Any attempt by the
	       Text widget to resize itself is always sub-
	       ject to the constraints imposed by its



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	       parent.	The values XawtextResizeNever, Xaw-
	       textResizeWidth, XawtextResizeHeight, and
	       XawtextResizeBoth are all acceptable for this
	       resource.  A converter is registered for this
	       resource that will convert the following
	       strings: never, height, width, and both.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

scrollHorizontal
scrollVertical These resources control the placement of
	       scrollbars on the left and bottom edge of the
	       text widget.  These resources accept the val-
	       ues XawtextScrollAlways, XawtextScrollWhen-
	       Needed, and XawtextScrollNever.	A converter
	       is registered for this resource that will
	       convert the following strings: always, never,
	       and whenNeeded.	If XawtextScrollWhenNeeded
	       is specified, the appropriate scrollbar will
	       only appear when there is text in the buffer
	       that is not able to fit within the bounds of
	       the current window.  The scrollbar will dis-
	       appear when the text once again fits within
	       the window.

selectTypes    Specifies the selection type array that is
	       used when multi-click is activated (see Text
	       Selections for Application Programmers for
	       details).  This resource is used in place,
	       and must not be freed until the widget is
	       destroyed.  There is no type converter regis-
	       tered for this resource, so it may not be set
	       from the resource manager.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

textSink
textSource     These are the TextSink or TextSource objects
	       used by this widget.  When using the Text
	       widget these MUST be set by the application
	       programmer.

translations   The event bindings associated with this wid-
	       get.

wrap	       When the text in any one line is wider than
	       the window there are several possible
	       actions.  This resource allows the user to
	       decide what will happen.  The accepted values
	       for this resource are XawtextWrapNever,



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	       XawtextWrapLine, and XawtextWrapWord.  With
	       XawtextWrapLine all text that is beyond the
	       right edge of the window will be displayed on
	       the next line.  With XawtextWrapWord the same
	       action occurs but the text is broken at a
	       word boundary if possible.  If no wrapping is
	       enabled then the text will extend off the
	       edge of the window, and a small rectangle
	       will be painted in the right margin to alert
	       the user that this line is too long.  A con-
	       verter is registered for this resource that
	       will convert the following strings: never,
	       word, and line.

unrealizeCallback
	       A list of callback functions which will be
	       executed when the Text widget is unrealized.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

5.10.  TextSrc Object



Application Header file<X11/Xaw/TextSrc.h>
Class Header file   <X11/Xaw/TextSrcP.h>
Class		    textSrcObjectClass
Class Name	    TextSrc
Superclass	    Object


The TextSrc object is the root object for all text sources.
Any new text source objects should be subclasses of the
TextSrc Object.  The TextSrc Class contains all methods the
Text widget expects a text source to export.

Since all text sources will have some resources in common
the TextSrc defines a few new resources.

5.10.1.  Resources

When creating an TextSrc object instance, the following
resources are retrieved from the argument list or from the
resource database:


-----------------------------------------------------------------------------
Name		  Class        Type		Notes	Default Value
-----------------------------------------------------------------------------
destroyCallback   Callback     XtCallbackList		NULL





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-----------------------------------------------------------------------------
Name		  Class        Type		Notes	Default Value
-----------------------------------------------------------------------------
editType	  EditType     EditMode 		NULL
-----------------------------------------------------------------------------


destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

editType       This is the type of editing that will be
	       allowed in this text widget.  Legal values
	       are XawtextRead, XawtextEdit, and XawtextAp-
	       pend.  A converter is registered for this
	       resource that will convert the following
	       strings: read, edit, and append.

5.10.2.  Subclassing the TextSrc

The only purpose of the TextSrc Object is to be subclassed.
It contains the minimum set of class methods that all text
sources must have.  All class methods of the TextSrc must be
defined, as the Text widget uses them all.  While all may be
inherited, the direct descendant of TextSrc must specify
some of them as TextSrc does not contain enough information
to be a valid text source by itself.  Do not try to use the
TextSrc as a valid source for the Text widget; it is not
intended to be used as a source by itself and bad things
will probably happen.

--------------------------------------------------------------------------------------------
Function	   Inherit with 	       Public Interface 	       must specify
--------------------------------------------------------------------------------------------
Read		   XtInheritRead	       XawTextSourceRead	       yes
Replace 	   XtInheritReplace	       XawTextSourceReplace	       no
Scan		   XtInheritScan	       XawTextSourceScan	       yes
Search		   XtInheritSearch	       XawTextSourceSearch	       no
SetSelection	   XtInheritSetSelection       XawTextSourceSetSelection       no
ConvertSelection   XtInheritConvertSelection   XawTextSourceConvertSelection   no
--------------------------------------------------------------------------------------------


5.10.2.1.  Reading Text.

To read the text in a text source use the Read function:

XawTextPosition Read(w, pos, text_return, length)
Widget w;
XawTextPosition pos;
XawTextBlock *text_return;
int length;





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w	  Specifies the TextSrc object.

pos	  Specifies the position of the first character to
	  be read from the text buffer.

text	  Returns the text read from the source.

length	  Specifies the maximum number of characters the
	  TextSrc should return to the application in
	  text_return.

This function returns the actual number of characters read
from the text buffer.  The function is not required to
return length characters if that many characters are in the
file, it may break at any point that is convenient to the
internal structure of the source.  It may take several calls
to Read before the desired portion of the text buffer is
fully retrieved.

5.10.2.2.  Replacing Text.

To replace or edit the text in a text buffer use the Replace
function:

XawTextPosition Replace(w, start, end, text)
Widget w;
XawTextPosition start, end;
XawTextBlock *text;


w	  Specifies the TextSrc object.

start	  Specifies the position of the first character to
	  be removed from the text buffer.  This is also the
	  location to begin inserting the new text.

end	  Specifies the position immediately after the last
	  character to be removed from the text buffer.

text	  Specifies the text to be added to the text source.

This function can return any of the following values:

XawEditDone The text replacement was successful.

XawPositionError
	    The edit mode is XawtextAppend and start is not
	    the last character of the source.

XawEditError
	    Either the Source was read-only or the range to
	    be deleted is larger than the length of the
	    Source.




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The Replace arguments start and end represent the text
source character positions for the existing text that is to
be replaced by the text in the text block.  The characters
from start up to but not including end are deleted, and the
buffer specified by the text block is inserted in their
place.	If start and end are equal, no text is deleted and
the new text is inserted after start.

5.10.2.3.  Scanning the TextSrc

To search the text source for one of the predefined boundary
types use the Scan function:

XawTextPosition Scan(w, position, type, dir, count, include)
Widget w;
XawTextPosition position;
XawTextScanType type;
XawTextScanDirection dir;
int count;
Boolean include;


w	  Specifies the TextSrc object.

position  Specifies the position to begin scanning the
	  source.

type	  Specifies the type of boundary to scan for, may be
	  one of: XawstPosition, XawstWhiteSpace, XawstEOL,
	  XawstParagraph, XawstAll.  The exact meaning of
	  these boundaries is left up to the individual text
	  source.

dir	  Specifies the direction to scan, may be either
	  XawsdLeft to search backward, or XawsdRight to
	  search forward.

count	  Specifies the number of boundaries to scan for.

include   Specifies whether the boundary itself should be
	  included in the scan.

The Scan function returns the position in the text source of
the desired boundary.  It is expected to return a valid
address for all calls made to it, thus if a particular
request is made that would take the text widget beyond the
end of the source it must return the position of that end.

5.10.2.4.  Searching through a TextSrc

To search for a particular string use the Search function.






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XawTextPosition Search(w, position, dir, text)
Widget w;
XawTextPosition position;
XawTextScanDirection dir;
XawTextBlock *text;


w	  Specifies the TextSrc object.

position  Specifies the position to begin the search.

dir	  Specifies the direction to search, may be either
	  XawsdLeft to search backward, or XawsdRight to
	  search forward.

text	  Specifies a text block containing the text to
	  search for.

This function will search through the text buffer attempting
to find a match for the string in the text block.  If a
match is found in the direction specified, then the charac-
ter location of the first character in the string is
returned.  If no text was found then XawTextSearchError is
returned.

5.10.2.5.  Text Selections

While many selection types are handled by the Text widget,
text sources may have selection types unknown to the Text
widget.  When a selection conversion is requested by the X
server the Text widget will first call the ConvertSelection
function, to attempt the selection conversion.

Boolean ConvertSelections(w, selection, target, type, value_return, length_return, format_return)
Widget w;
Atom *selection, *target, *type;
caddr_t *value_return;
unsigned long *length_return;
int *format_return;


w	  Specifies the TextSrc object.

selection Specifies the type of selection that was requested
	  (e.g. PRIMARY).

target	  Specifies the type of the selection that has been
	  requested, which indicates the desired information
	  about the selection (e.g. Filename, Text, Window).

type	  Specifies a pointer to the atom into which the
	  property type of the converted value of the selec-
	  tion is to be stored.  For instance, either file
	  name or text might have property type XA_STRING.



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value_return
	  Returns a pointer into which a pointer to the con-
	  verted value of the selection is to be stored.
	  The selection owner is responsible for allocating
	  this storage.  The memory is considered owned by
	  the toolkit, and is freed by XtFree when the
	  Intrinsics selection mechanism is done with it.

length_return
	  Returns a pointer into which the number of ele-
	  ments in value is to be stored.  The size of each
	  element is determined by format.

format_return
	  Returns a pointer into which the size in bits of
	  the data elements of the selection value is to be
	  stored.

If this function returns True then the Text widget will
assume that the source has taken care of converting the
selection, Otherwise the Text widget will attempt to convert
the selection itself.


If the source needs to know when the text selection is modi-
fied it should define a SetSelection procedure:

void SetSelection(w, start, end, selection)
Widget w;
XawTextPosition start, end;
Atom selection;


w	  Specifies the TextSrc object.

start	  Specifies the character position of the beginning
	  of the new text selection.

end	  Specifies the character position of the end of the
	  new text selection.

selection Specifies the type of selection that was requested
	  (e.g. PRIMARY).

5.11.  TextSink Object



Application Header file<X11/Xaw/TextSink.h>
Class Header file   <X11/Xaw/TextSinkP.h>
Class		    textSinkObjectClass
Class Name	    TextSink
Superclass	    Object




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The TextSink object is the root object for all text sinks.
Any new text sink objects should be subclasses of the
TextSink Object.  The TextSink Class contains all methods
that the Text widget expects a text sink to export.

Since all text sinks will have some resources in common, the
TextSink defines a few new resources.

5.11.1.  Resources

When creating an TextSink object instance, the following
resources are retrieved from the argument list or from the
resource database:


-----------------------------------------------------------------------------
Name		  Class        Type		Notes	Default Value
-----------------------------------------------------------------------------
background	  Background   Pixel			XtDefaultBackground
destroyCallback   Callback     XtCallbackList		NULL
foreground	  Foreground   Pixel			XtDefaultForeground
-----------------------------------------------------------------------------


background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

foreground     A pixel value which indexes the Text widget's
	       colormap to derive the foreground color used
	       by the text sink.

5.11.2.  Subclassing the TextSink

The only purpose of the TextSink Object is to be subclassed.
It contains the minimum set of class methods that all text
sinks must have.  While all may be inherited, the direct
descendant of TextSink must specify some of them as TextSink
does contain enough information to be a valid text sink by
itself.  Do not try to use the TextSink as a valid sink for
the Text widget; it is not intended to be used as a sink by
itself.

---------------------------------------------------------------------------------------------
Function	    Inherit with		 Public Interface		must specify
---------------------------------------------------------------------------------------------
DisplayText	    XtInheritDisplayText	 XawTextSinkDisplayText 	yes
InsertCursor	    XtInheritInsertCursor	 XawTextSinkInsertCursor	yes
ClearToBackground   XtInheritClearToBackground	 XawTextSinkClearToBackground	no




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---------------------------------------------------------------------------------------------
Function	    Inherit with		 Public Interface		must specify
---------------------------------------------------------------------------------------------
FindPosition	    XtInheritFindPosition	 XawTextSinkFindPosition	yes
FindDistance	    XtInheritFindDistance	 XawTextSinkFindDistance	yes
Resolve 	    XtInheritResolve		 XawTextSinkResolve		yes
MaxLines	    XtInheritMaxLines		 XawTextSinkMaxLines		no
MaxHeight	    XtInheritMaxHeight		 XawTextSinkMaxHeight		no
SetTabs 	    XtInheritSetTabs		 XawTextSinkSetTabs		no
GetCursorBounds     XtInheritGetCursorBounds	 XawTextSinkGetCursorBounds	yes
---------------------------------------------------------------------------------------------


5.11.2.1.  Displaying Text

To display a section of the text buffer contained in the
text source use the function DisplayText:

void DisplayText(w, x, y, pos1, pos2, highlight)
      Widget w;
      Position x, y;
      XawTextPosition pos1, pos2;
      Boolean highlight;


w	  Specifies the TextSink object.

x	  Specifies the x location to start drawing the
	  text.

y	  Specifies the y location to start drawing text.

pos1	  Specifies the location within the text source of
	  the first character to be printed.

pos2	  Specifies the location within the text source of
	  the last character to be printed.

highlight Specifies whether or not to paint the text region
	  highlighted.

The Text widget will only pass one line at a time to the
text sink, so this function does not need to know how to
line feed the text.  It is acceptable for this function to
just ignore Carriage Returns.  x and y denote the upper left
hand corner of the first character to be displayed.

5.11.2.2.  Displaying the Insert Point

The function that controls the display of the text cursor is
InsertCursor.  This function will be called whenever the
text widget desires to change the state of, or move the
insert point.




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void InsertCursor(w, x, y, state)
      Widget w;
      Position x, y;
      XawTextInsertState state;


w	  Specifies the TextSink object.

x	  Specifies the x location of the cursor in Pixels.

y	  Specifies the y location of the cursor in Pixels.

state	  Specifies the state of the cursor, may be one of
	  XawisOn or XawisOff.

X and y denote the upper left hand corner of the insert
point.

5.11.2.3.  Clearing Portions of the Text window

To clear a portion of the Text window to its background
color, the Text widget will call ClearToBackground.  The
TextSink object already defines this function as calling
XClearArea on the region passed.  This behavior will be used
if you specify XtInheritClearToBackground for this method.

void ClearToBackground(w, x, y, width, height)
      Widget w;
      Position x, y;
      Dimension width, height;


w	  Specifies the TextSink object.

x	  Specifies the x location, in pixels, of the Region
	  to clear.

y	  Specifies the y location, in pixels, of the Region
	  to clear.

width	  Specifies the width, in pixels, of the Region to
	  clear.

height	  Specifies the height, in pixels, of the Region to
	  clear.

X and y denote the upper left hand corner of region to
clear.

5.11.2.4.  Finding a Text Position Given Pixel Values

To find the text character position that will be rendered at
a given x location the Text widget uses the function FindPo-
sition:



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void FindPosition(w, fromPos, fromX, width, stopAtWordBreak, pos_return, width_return, height_return)
      Widget w;
      XawTextPosition fromPos;
      int fromX, width;
      Boolean stopAtWordBreak;
      XawTextPosition *pos_return;
      int *width_return, *height_return;


w	    Specifies the TextSink object.

fromPos     Specifies a reference position, usually the
	    first character in this line.  This character is
	    always to the left of the desired character
	    location.

fromX	    Specifies the distance that the left edge of
	    fromPos is from the left edge of the window.
	    This is the reference x location for the refer-
	    ence position.

width	    Specifies the distance, in pixels, from the ref-
	    erence position to the desired character posi-
	    tion.

stopAtWordBreak
	    Specifies whether or not the position that is
	    returned should be forced to be on a word bound-
	    ary.

pos_return  Returns the character position that corresponds
	    to the location that has been specified, or the
	    work break immediately to the left of the posi-
	    tion if stopAtWordBreak is True.

width_return
	    Returns the actual distance between fromPos and
	    pos_return.

height_return
	    Returns the maximum height of the text between
	    fromPos and pos_return.

This function need make no attempt to deal with line feeds.
The text widget will only call it one line at a time.


Another means of finding a text position is provided by the
Resolve function:








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void Resolve(w, fromPos, fromX, width, pos_return)
      Widget w;
      XawTextPosition fromPos;
      int fromX, width;
      XawTextPosition *pos_return;


w	  Specifies the TextSink object.

fromPos   Specifies a reference position, usually the first
	  character in this line.  This character is always
	  to the left of the desired character location.

fromX	  Specifies the distance that the left edge of
	  fromPos is from the left edge of the window.	This
	  is the reference x location for the reference
	  position.

width	  Specifies the distance, in pixels, from the refer-
	  ence position to the desired character position.

pos_return
	  Returns the character position that corresponds to
	  the location that has been specified, or the word
	  break immediately to the left if stopAtWordBreak
	  is True.

This function need make no attempt to deal with line feeds.
The text widget will only call it one line at a time.  This
is a more convenient interface to the FindPosition function,
and provides a subset of its functionality.

5.11.2.5.  Finding the Distance Between two Text Positions

To find the distance in pixels between two text positions on
the same line use the function FindDistance.

void FindDistance(w, fromPos, fromX, toPos, width_return, pos_return, height_return)
      Widget w;
      XawTextPosition fromPos, toPos;
      int fromX;
      XawTextPosition *pos_return;
      int *width_return, *height_return;


w	  Specifies the TextSink object.

fromPos   Specifies the text buffer position, in characters,
	  of the first position.

fromX	  Specifies the distance that the left edge of
	  fromPos is from the left edge of the window.	This
	  is the reference x location for the reference
	  position.



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toPos	  Specifies the text buffer position, in characters,
	  of the second position.

resWidth  Return the actual distance between fromPos and
	  pos_return.

resPos	  Returns the character position that corresponds to
	  the actual character position used for toPos in
	  the calculations.  This may be different than
	  toPos, for example if fromPos and toPos are on
	  different lines in the file.

height_return
	  Returns the maximum height of the text between
	  fromPos and pos_return.

This function need make no attempt to deal with line feeds.
The Text widget will only call it one line at a time.

5.11.2.6.  Finding the Size of the Drawing area

To find the maximum number of lines that will fit into the
current Text widget, use the function MaxLines.  The
TextSink already defines this function to compute the maxi-
mum number of lines by using the height of font.

int MaxLines(w, height)
      Widget w;
      Dimension height;


w	  Specifies the TextSink object.

height	  Specifies the height of the current drawing area.

Returns the maximum number of lines that will fit in height.


To find the height required for a given number of text
lines, use the function MaxHeight.  The TextSink already
defines this function to compute the maximum height of the
window by using the height of font.

int MaxHeight(w, lines)
      Widget w;
      int lines;


w	  Specifies the TextSink object.

height	  Specifies the height of the current drawing area.

Returns the height that will be taken up by the number of
lines passed.



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5.11.2.7.  Setting the Tab Stops

To set the tab stops for a text sink use the SetTabs func-
tion.  The TextSink already defines this function to set the
tab x location in pixels to be the number of characters
times the figure width of font.

void SetTabs(w, tab_count, tabs)
      Widget w;
      int tab_count, *tabs;


w	  Specifies the TextSink object.

tab_count Specifies the number of tabs passed in tabs.

tabs	  Specifies the position, in characters, of the tab
	  stops.

This function is responsible for the converting character
positions passed to it into whatever internal positions the
TextSink uses for tab placement.

5.11.2.8.  Getting the Insert Point's Size and Location

To get the size and location of the insert point use the
GetCursorBounds function.

void GetCursorBounds(w, rect_return)
Widget w;
XRectangle *rect_return;


w	  Specifies the TextSinkObject.

rect_return
	  Returns the location and size of the insert point.

Rect will be filled with the current size and location of
the insert point.

















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			 Chapter 6

	      Composite and Constraint Widgets




These widgets may contain arbitrary widget children.  They
implement a policy for the size and location of their chil-
dren.

Box	  This widget will pack its children as tightly as
	  possible in non-overlapping rows.

Dialog	  An implementation of a commonly used interaction
	  semantic to prompt for auxiliary input from the
	  user, such as a filename.

Form	  A more sophisticated layout widget that allows the
	  children to specify their positions relative to
	  the other children, or to the edges of the Form.

Paned	  Allows children to be tiled vertically or horizon-
	  tally.  Controls are also provided to allow the
	  user to dynamically resize the individual panes.

Porthole  Allows viewing of a managed child which is as
	  large as, or larger than its parent, typically
	  under control of a Panner widget.

Tree	  Provides geometry management of widgets arranged
	  in a directed, acyclic graph.

Viewport  Consists of a frame, one or two scrollbars, and an
	  inner window.  The inner window can contain all
	  the data that is to be displayed.  This inner win-
	  dow will be clipped by the frame with the scroll-
	  bars controlling which section of the inner window
	  is currently visible.


6.0.1.	A Brief Note on Geometry Management

The geometry management semantics provided by the X Toolkit
give full control of the size and position of a widget to
the parent of that widget.  While the children are allowed
to request a certain size or location, it is the parent who
makes the final decision.  Many of the composite widgets
here will deny any geometry request from their children by
default.  If a child widget is not getting the expected size
or location, it is most likely the parent disallowing a
request, or implementing semantics slightly different than



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those expected by the application programmer.

If the application wishes to change the size or location of
any widget it should make a call to XtSetValues.  This will
allow the widget to ask its parent for the new size or loca-
tion.  As noted above the parent is allowed to refuse this
request, and the child must live with the result.  If the
application is unable to achieve the desired semantics, then
perhaps it should use a different composite widget.  Under
no circumstances should an application programmer resort to
XtMoveWidget or XtResizeWidget; these functions are exclu-
sively for the use of Composite widget implementors.

For more information on geometry management consult the X
Toolkit Intrinsics -- C Language Interface.



6.1.  Box Widget



Application Header file<X11/Xaw/Box.h>
Class Header file   <X11/Xaw/BoxP.h>
Class		    boxWidgetClass
Class Name	    Box
Superclass	    Composite



The Box widget provides geometry management of arbitrary
widgets in a box of a specified dimension.  The children are
rearranged when resizing events occur either on the Box or
its children, or when children are managed or unmanaged.
The Box widget always attempts to pack its children as
tightly as possible within the geometry allowed by its par-
ent.

Box widgets are commonly used to manage a related set of
buttons and are often called ButtonBox widgets, but the
children are not limited to buttons.  The Box's children are
arranged on a background that has its own specified dimen-
sions and color.

6.1.1.	Resources

When creating a Box widget instance, the following resources
are retrieved from the argument list or from the resource
database:








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----------------------------------------------------------------------------
Name		 Class		  Type		  NotesDefault Value
----------------------------------------------------------------------------
accelerators	 Accelerators	  AcceleratorTable     NULL
ancestorSensitiveAncestorSensitiveBoolean	  D    True
background	 Background	  Pixel 	       XtDefaultBackground
backgroundPixmap Pixmap 	  Pixmap	       XtUnspecifiedPixmap
borderColor	 BorderColor	  Pixel 	       XtDefaultForeground
borderPixmap	 Pixmap 	  Pixmap	       XtUnspecifiedPixmap
borderWidth	 BorderWidth	  Dimension	       1
children	 ReadOnly	  WidgetList	  R    NULL
colormap	 Colormap	  Colormap	       Parent's Colormap
depth		 Depth		  int		  C    Parent's Depth
destroyCallback  Callback	  XtCallbackList       NULL
height		 Height 	  Dimension	  A    see Layout Semantics
hSpace		 HSpace 	  Dimension	       4
mappedWhenManagedMappedWhenManagedBoolean	       True
numChildren	 ReadOnly	  Cardinal	  R    0
orientation	 Orientation	  Orientation	       XtorientVertical
screen		 Screen 	  Screen	  R    Parent's Screen
sensitive	 Sensitive	  Boolean	       True
vSpace		 VSpace 	  Dimension	       4
translations	 Translations	  TranslationTable     NULL
width		 Width		  Dimension	  A    see Layout Semantics
x		 Position	  Position	       0
y		 Position	  Position	       0
----------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.





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borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

children       A list of all this composite widget's current
	       children.

colormap       The colormap that this widget will use.

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

height
width	       The height and width of this widget in pix-
	       els.

hSpace
vSpace	       The amount of space, in pixels, to leave
	       between the children.  This resource speci-
	       fies the amount of space left between the
	       outermost children and the edge of the box.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

numChildren    The number of children in this composite wid-
	       get.

orientation    Specifies whether the preferred shape of the
	       box (i.e. the result returned by the
	       query_geometry class method) is tall and nar-
	       row XtorientVertical or short and wide Xtori-
	       entHorizontal.  When the Box is a child of a
	       parent which enforces width constraints, it
	       is usually better to specify XtorientVertical
	       (the default).  When the parent enforces
	       height constraints, it is usually better to
	       specify XtorientHorizontal.  A converter is
	       registered for this resource that will con-
	       vert the following strings: horizontal and
	       vertical.



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screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

6.1.2.	Layout Semantics

Each time a child is managed or unmanaged, the Box widget
will attempt to reposition the remaining children to compact
the box.  Children are positioned in order left to right,
top to bottom.	The packing algorithm used depends on the
orientation of the Box.

XtorientVertical
	       When the next child does not fit on the cur-
	       rent row, a new row is started.	If a child
	       is wider than the width of the box, the box
	       will request a larger width from its parent
	       and will begin the layout process from the
	       beginning if a new width is granted.

XtorientHorizontal
	       When the next child does not fit on the cur-
	       rent row, the Box widens if possible (so as
	       to keep children on a single row); otherwise
	       a new row is started.

After positioning all children, the Box widget attempts to
shrink its own size to the minimum dimensions required for
the layout.

6.2.  Dialog Widget



Application Header file<X11/Xaw/Dialog.h>
Class Header file   <X11/Xaw/DialogP.h>
Class		    dialogWidgetClass
Class Name	    Dialog
Superclass	    Form







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The Dialog widget implements a commonly used interaction
semantic to prompt for auxiliary input from a user.  For
example, you can use a Dialog widget when an application
requires a small piece of information, such as a filename,
from the user.	A Dialog widget, which is simply a special
case of the Form widget, provides a convenient way to create
a preconfigured form.

The typical Dialog widget contains three areas.  The first
line contains a description of the function of the Dialog
widget, for example, the string Filename:.  The second line
contains an area into which the user types input.  The third
line can contain buttons that let the user confirm or cancel
the Dialog input.  Any of these areas may be omitted by the
application.

6.2.1.	Resources

When creating a Dialog widget instance, the following
resources are retrieved from the argument list or the
resource database:

--------------------------------------------------------------------------------------------
Name		 Class		  Type		  NotesDefault Value
--------------------------------------------------------------------------------------------
accelerators	 Accelerators	  AcceleratorTable     NULL
ancestorSensitiveAncestorSensitiveBoolean	  D    True
background	 Background	  Pixel 	       XtDefaultBackground
backgroundPixmap Pixmap 	  Pixmap	       XtUnspecifiedPixmap
borderColor	 BorderColor	  Pixel 	       XtDefaultForeground
borderPixmap	 Pixmap 	  Pixmap	       XtUnspecifiedPixmap
borderWidth	 BorderWidth	  Dimension	       1
children	 ReadOnly	  WidgetList	  R    NULL
colormap	 Colormap	  Colormap	       Parent's Colormap
defaultDistance  Thickness	  int		       4
depth		 Depth		  int		  C    Parent's Depth
destroyCallback  Callback	  XtCallbackList       NULL
height		 Height 	  Dimension	  A    Enough space to contain all children
icon		 Icon		  Bitmap	       None
label		 Label		  String	       "label"
mappedWhenManagedMappedWhenManagedBoolean	       True
numChildren	 ReadOnly	  Cardinal	  R    0
screen		 Screen 	  Screen	  R    Parent's Screen
sensitive	 Sensitive	  Boolean	       True
translations	 Translations	  TranslationTable     NULL
value		 Value		  String	       no value widget
width		 Width		  Dimension	  A    Enough space to contain all children
x		 Position	  Position	       0
y		 Position	  Position	       0
--------------------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event



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	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

children       A list of all this composite widget's current
	       children.

colormap       The colormap that this widget will use.

defaultDistance
	       The default internal spacing for the chil-
	       dren.  This is the default value for the con-
	       straint resources horizDistance and vertDis-
	       tance.

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

height
width	       The height and width of this widget in pix-
	       els.



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icon	       A pixmap image to be displayed immediately to
	       the left of the Dialog widget's label.

label	       A string to be displayed at the top of the
	       Dialog widget.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

numChildren    The number of children in this composite wid-
	       get.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

translations   The event bindings associated with this wid-
	       get.

value	       An initial value for the string field that
	       the user will enter text into.  By default,
	       no text entry field is available to the user.
	       Specifying an initial value for value acti-
	       vates the text entry field.  If string input
	       is desired, but no initial value is to be
	       specified then set this resource to "" (empty
	       string).

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

6.2.2.	Constraint Resources

Each child of the Dialog widget may request special layout
resources be applied to it.  These constraint resources
allow the Dialog widget's children to specify individual
layout requirements.


------------------------------------------------------------------------------
Name		Class	     Type	   Notes   Default Value
------------------------------------------------------------------------------
bottom		Edge	     XawEdgeType	   XawRubber
fromHoriz	Widget	     Widget		   NULL (left edge of Dialog)
fromVert	Widget	     Widget		   NULL (top edge of Dialog)
horizDistance	Thickness    int		   defaultDistance resource




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------------------------------------------------------------------------------
Name		Class	     Type	   Notes   Default Value
------------------------------------------------------------------------------
left		Edge	     XawEdgeType	   XawRubber
resizable	Boolean      Boolean		   FALSE
right		Edge	     XawEdgeType	   XawRubber
top		Edge	     XawEdgeType	   XawRubber
vertDistance	Thickness    int		   defaultDistance resource
------------------------------------------------------------------------------


bottom
left
right
top	       What to do with this edge of the child when
	       the parent is resized.  This resource may be
	       any edgeType.  See Layout Semantics for
	       details.

fromHoriz
fromVert       Which widget this child should be placed
	       underneath (or to the right of).  If a value
	       of NULL is specified then this widget will be
	       positioned relative to the edge of the par-
	       ent.

horizDistance
vertDistance   The amount of space, in pixels, between this
	       child and its left or upper neighbor.

resizable      If this resource is False then the parent
	       widget will ignore all geometry request made
	       by this child.  The parent may still resize
	       this child itself, however.

6.2.3.	Layout Semantics

The Dialog widget uses two different sets of layout seman-
tics.  One is used when initially laying out the children.
The other is used when the Dialog is resized.

The first layout method uses the fromVert and fromHoriz
resources to place the children of the Dialog.	A single
pass is made through the Dialog widget's children in the
order that they were created.  Each child is then placed in
the Dialog widget below or to the right of the widget speci-
fied by the fromVert and fromHoriz resources.  The distance
the new child is placed from its left or upper neighbor is
determined by the horizDistance and vertDistance resources.
This implies some things about how the order of creation
affects the possible placement of the children.  The Form
widget registers a string to widget converter which does not
postpone conversion and does not cache conversion results.




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The second layout method is used when the Dialog is resized.
It does not matter what causes this resize, and it is possi-
ble for a resize to happen before the widget becomes visible
(due to constraints imposed by the parent of the Dialog).
This layout method uses the bottom, top, left, and right
resources.  These resources are used to determine what will
happen to each edge of the child when the Dialog is resized.
If a value of XawChain<something> is specified, the the edge
of the child will remain a fixed distance from the chain
edge of the Dialog.  For example if XawChainLeft is speci-
fied for the right resource of a child then the right edge
of that child will remain a fixed distance from the left
edge of the Dialog widget.  If a value of XawRubber is spec-
ified, that edge will grow by the same percentage that the
Dialog grew.  For instance if the Dialog grows by 50% the
left edge of the child (if specified as XawRubber will be
50% farther from the left edge of the Dialog).	One must be
very careful when specifying these resources, for when they
are specified incorrectly children may overlap or completely
occlude other children when the Dialog widget is resized.


--------------------------------------------------------------------------------------
Edge Type	  Resource Name   Description
--------------------------------------------------------------------------------------
XawChainBottom	  ChainBottom	  Edge remains a fixed distance from bottom of Dialog
XawChainLeft	  ChainLeft	  Edge remains a fixed distance from left of Dialog
XawChainRight	  ChainRight	  Edge remains a fixed distance from right of Dialog
XawChainTop	  ChainTop	  Edge remains a fixed distance from top of Dialog
XawRubber	  Rubber	  Edges will move a proportional distance
--------------------------------------------------------------------------------------


6.2.3.1.  Example

If you wish to force the Dialog to never resize one or more
of its children then set left and right to XawChainLeft and
top and bottom to XawChainTop.	This will cause the child to
remain a fixed distance from the top and left edges of the
Dialog, and to never resize.

6.2.3.2.  Special Considerations

The Dialog widget automatically sets the top and bottom
resources for all Children that are subclasses of the Com-
mand widget, as well as the widget children that are used to
contain the label, value, and icon.  This policy allows the
buttons at the bottom of the Dialog to interact correctly
with the predefined children, and makes it possible for a
client to simply create and manage a new Command button
without having to specify its constraints.

The Dialog will also set fromLeft to the last button in the
Dialog for each new button added to the Dialog widget.



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The automatically added constraints cannot be overridden, as
they are policy decisions of the Dialog widget.  If a more
flexible Dialog is desired, the application is free to use
the Form widget to create its own Dialog policy.

6.2.4.	Automatically Created Children.

The Dialog uses Label widgets to contain the label and icon.
These widgets are named label and icon respectively.  The
Dialog value is contained in an AsciiText widget whose name
is value.  Using XtNameToWidget the application can change
those resources associated with each of these widgets that
are not available through the Dialog widget itself.


6.2.5.	Convenience Routines

To return the character string in the text field, use
XawDialogGetValueString.

String XawDialogGetValueString(w)
     Widget w;


w	  Specifies the Dialog widget.

This function returns a copy of the value string of the Dia-
log widget.  This string is allocated by the AsciiText wid-
get and will remain valid and unchanged until another call
to XawDialogGetValueString or an XtGetValues call on the
value widget, when the string will be automatically freed,
and a new string is returned.  This string may be freed ear-
lier by calling the function XawAsciiSourceFreeString.


To add a new button to the Dialog widget use XawDialogAd-
dButton.

void XawDialogAddButton(w, name, func, client_data)
     Widget w;
     String name;
     XtCallbackProc func;
     XtPointer client_data;


w	  Specifies the Dialog widget.

name	  Specifies the name of the new Command button to be
	  added to the Dialog.

func	  Specifies a callback function to be called when
	  this button is activated.  If NULL is specified
	  then no callback is added.




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client_data
	  Specifies the client_data to be passed to the
	  func.

This function is merely a shorthand for the code sequence:


{
	  Widget button = XtCreateManagedWidget(name, commandWidgetClass, w, NULL, ZERO);
	  XtAddCallback(button, XtNcallback, func, client_data);
}



6.3.  Form Widget



Application Header file<X11/Xaw/Form.h>
Class Header file   <X11/Xaw/FormP.h>
Class		    formWidgetClass
Class Name	    Form
Superclass	    Constraint



The Form widget can contain an arbitrary number of children
or subwidgets.	The Form provides geometry management for
its children, which allows individual control of the posi-
tion of each child.  Any combination of children can be
added to a Form.  The initial positions of the children may
be computed relative to the positions of previously created
children.  When the Form is resized, it computes new posi-
tions and sizes for its children.  This computation is based
upon information provided when a child is added to the Form.

The default width of the Form is the minimum width needed to
enclose the children after computing their initial layout,
with a margin of defaultDistance at the right and bottom
edges.	If a width and height is assigned to the Form that
is too small for the layout, the children will be clipped by
the right and bottom edges of the Form.

6.3.1.	Resources

When creating an Form widget instance, the following
resources are retrieved from the argument list or from the
resource database:









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--------------------------------------------------------------------------------------------
Name		 Class		  Type		  NotesDefault Value
--------------------------------------------------------------------------------------------
accelerators	 Accelerators	  AcceleratorTable     NULL
ancestorSensitiveAncestorSensitiveBoolean	  D    True
background	 Background	  Pixel 	       XtDefaultBackground
backgroundPixmap Pixmap 	  Pixmap	       XtUnspecifiedPixmap
borderColor	 BorderColor	  Pixel 	       XtDefaultForeground
borderPixmap	 Pixmap 	  Pixmap	       XtUnspecifiedPixmap
borderWidth	 BorderWidth	  Dimension	       1
children	 ReadOnly	  WidgetList	  R    NULL
colormap	 Colormap	  Colormap	       Parent's Colormap
defaultDistance  Thickness	  int		       4
depth		 Depth		  int		  C    Parent's Depth
destroyCallback  Callback	  XtCallbackList       NULL
height		 Height 	  Dimension	  A    Enough space to contain all children
mappedWhenManagedMappedWhenManagedBoolean	       True
numChildren	 ReadOnly	  Cardinal	  R    0
screen		 Screen 	  Screen	  R    Parent's Screen
sensitive	 Sensitive	  Boolean	       True
translations	 Translations	  TranslationTable     NULL
width		 Width		  Dimension	  A    Enough space to contain all children
x		 Position	  Position	       0
y		 Position	  Position	       0
--------------------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.



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borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

children       A list of all this composite widget's current
	       children.

colormap       The colormap that this widget will use.

defaultDistance
	       The default internal spacing for the chil-
	       dren.  This is the default value for the con-
	       straint resources horizDistance and vertDis-
	       tance.

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

height
width	       The height and width of this widget in pix-
	       els.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

numChildren    The number of children in this composite wid-
	       get.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.






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6.3.2.	Constraint Resources

Each child of the Form widget may request special layout
resources be applied to it.  These constraint resources
allow the Form widget's children to specify individual lay-
out requirements.



----------------------------------------------------------------------------
Name		Class	     Type	   Notes   Default Value
----------------------------------------------------------------------------
bottom		Edge	     XawEdgeType	   XawRubber
fromHoriz	Widget	     Widget		   NULL (left edge of Form)
fromVert	Widget	     Widget		   NULL (top edge of Form)
horizDistance	Thickness    int		   defaultDistance resource
left		Edge	     XawEdgeType	   XawRubber
resizable	Boolean      Boolean		   FALSE
right		Edge	     XawEdgeType	   XawRubber
top		Edge	     XawEdgeType	   XawRubber
vertDistance	Thickness    int		   defaultDistance resource
----------------------------------------------------------------------------


bottom
left
right
top	       What to do with this edge of the child when
	       the parent is resized.  This resource may be
	       any edgeType.  See Layout Semantics for
	       details.

fromHoriz
fromVert       Which widget this child should be placed
	       underneath (or to the right of).  If a value
	       of NULL is specified then this widget will be
	       positioned relative to the edge of the par-
	       ent.

horizDistance
vertDistance   The amount of space, in pixels, between this
	       child and its left or upper neighbor.

resizable      If this resource is False then the parent
	       widget will ignore all geometry request made
	       by this child.  The parent may still resize
	       this child itself, however.

6.3.3.	Layout Semantics

The Form widget uses two different sets of layout semantics.
One is used when initially laying out the children.  The
other is used when the Form is resized.




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The first layout method uses the fromVert and fromHoriz
resources to place the children of the Form.  A single pass
is made through the Form widget's children in the order that
they were created.  Each child is then placed in the Form
widget below or to the right of the widget specified by the
fromVert and fromHoriz resources.  The distance the new
child is placed from its left or upper neighbor is deter-
mined by the horizDistance and vertDistance resources.	This
implies some things about how the order of creation affects
the possible placement of the children.  The Form widget
registers a string to widget converter which does not post-
pone conversion and does not cache conversion results.

The second layout method is used when the Form is resized.
It does not matter what causes this resize, and it is possi-
ble for a resize to happen before the widget becomes visible
(due to constraints imposed by the parent of the Form).
This layout method uses the bottom, top, left, and right
resources.  These resources are used to determine what will
happen to each edge of the child when the Form is resized.
If a value of XawChain<something> is specified, the the edge
of the child will remain a fixed distance from the chain
edge of the Form.  For example if XawChainLeft is specified
for the right resource of a child then the right edge of
that child will remain a fixed distance from the left edge
of the Form widget.  If a value of XawRubber is specified,
that edge will grow by the same percentage that the Form
grew.  For instance if the Form grows by 50% the left edge
of the child (if specified as XawRubber will be 50% farther
from the left edge of the Form).  One must be very careful
when specifying these resources, for when they are specified
incorrectly children may overlap or completely occlude other
children when the Form widget is resized.


------------------------------------------------------------------------------------
Edge Type	  Resource Name   Description
------------------------------------------------------------------------------------
XawChainBottom	  ChainBottom	  Edge remains a fixed distance from bottom of Form
XawChainLeft	  ChainLeft	  Edge remains a fixed distance from left of Form
XawChainRight	  ChainRight	  Edge remains a fixed distance from right of Form
XawChainTop	  ChainTop	  Edge remains a fixed distance from top of Form
XawRubber	  Rubber	  Edges will move a proportional distance
------------------------------------------------------------------------------------


6.3.3.1.  Example

If you wish to force the Form to never resize one or more of
its children, then set left and right to XawChainLeft and
top and bottom to XawChainTop.	This will cause the child to
remain a fixed distance from the top and left edges of the
Form, and never to resize.




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6.3.4.	Convenience Routines

To force or defer a re-layout of the Form, use
XawFormDoLayout.

void XawFormDoLayout(w, do_layout)
     Widget w;
     Boolean do_layout;


w	  Specifies the Form widget.

do_layout Specifies whether the layout of the Form widget is
	  enabled (True) or disabled (False).

When making several changes to the children of a Form widget
after the Form has been realized, it is a good idea to dis-
able relayout until after all changes have been made.


6.4.  Paned Widget



Application Header file<X11/Xaw/Paned.h>
Class Header file   <X11/Xaw/PanedP.h>
Class		    panedWidgetClass
Class Name	    Paned
Superclass	    Constraint



The Paned widget manages children in a vertically or hori-
zontally tiled fashion.  The panes may be dynamically
resized by the user by using the grips that appear near the
right or bottom edge of the border between two panes.

The Paned widget may accept any widget class as a pane
except Grip.  Grip widgets have a special meaning for the
Paned widget, and adding a Grip as its own pane will confuse
the Paned widget.

6.4.1.	Using the Paned Widget

The grips allow the panes to be resized by the user.  The
semantics of how these panes resize is somewhat complicated,
and warrants further explanation here.	When the mouse
pointer is positioned on a grip and pressed, an arrow is
displayed that indicates the pane that is to be to be
resized.  While keeping the mouse button down, the user can
move the grip up and down (or left and right).	This, in
turn, changes the size of the pane.  The size of the Paned
widget will not change.   Instead, it chooses another pane
(or panes) to resize. For more details on which pane it



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chooses to resize, see Layout Semantics.

One pointer binding allows the border between two panes to
be moved, without affecting any of the other panes.  When
this occurs the pointer will change to an arrow that points
along the pane border.

The default bindings for the Paned widget's grips are:

-----------------------------------------------------------------------
Mouse button   Pane to Resize - Vertical   Pane to Resize - Horizontal
-----------------------------------------------------------------------
1 (left)       above the grip		   left of the grip
2 (middle)     adjust border		   adjust border
3 (right)      below the grip		   right of the grip
-----------------------------------------------------------------------


6.4.2.	Resources

When creating a Paned widget instance, the following
resources are retrieved from the argument list or the
resource database:


------------------------------------------------------------------------------------
Name		       Class		Type		NotesDefault Value
------------------------------------------------------------------------------------
accelerators	       Accelerators	AcceleratorTable     NULL
ancestorSensitive      AncestorSensitiveBoolean 	D    True
background	       Background	Pixel		     XtDefaultBackground
backgroundPixmap       Pixmap		Pixmap		     XtUnspecifiedPixmap
betweenCursor	       Cursor		Cursor		A    Depends on orientation
borderColor	       BorderColor	Pixel		     XtDefaultForeground
borderPixmap	       Pixmap		Pixmap		     XtUnspecifiedPixmap
borderWidth	       BorderWidth	Dimension	     1
children	       ReadOnly 	WidgetList	R    NULL
colormap	       Colormap 	Colormap	     Parent's Colormap
cursor		       Cursor		Cursor		     None
depth		       Depth		int		C    Parent's Depth
destroyCallback        Callback 	XtCallbackList	     NULL
gripCursor	       Cursor		Cursor		A    Depends on orientation
gripIndent	       GripIndent	Position	     10
gripTranslations       Translations	TranslationTable     see below
height		       Height		Dimension	A    Depends on orientation
horizontalBetweenCursorCursor		Cursor		     sb_up_arrow
horizontalGripCursor   Cursor		Cursor		     sb_h_double_arrow
internalBorderColor    BorderColor	Pixel		     XtDefaultForeground
internalBorderWidth    BorderWidth	Dimension	     1
leftCursor	       Cursor		Cursor		     sb_left_arrow
lowerCursor	       Cursor		Cursor		     sb_down_arrow
mappedWhenManaged      MappedWhenManagedBoolean 	     True
numChildren	       ReadOnly 	Cardinal	R    0




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------------------------------------------------------------------------------------
Name		       Class		Type		NotesDefault Value
------------------------------------------------------------------------------------
orientation	       Orientation	Orientation	     XtorientVertical
refigureMode	       Boolean		Boolean 	     True
rightCursor	       Cursor		Cursor		     sb_right_arrow
screen		       Screen		Screen		R    Parent's Screen
sensitive	       Sensitive	Boolean 	     True
translations	       Translations	TranslationTable     NULL
upperCursor	       Cursor		Cursor		     sb_up_arrow
verticalBetweenCursor  Cursor		Cursor		     sb_left_arrow
verticalGripCursor     Cursor		Cursor		     sb_v_double_arrow
width		       Width		Dimension	A    Depends on orientation
x		       Paned		Position	     0
y		       Paned		Position	     0
------------------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.




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children       A list of all this composite widget's current
	       children.

colormap       The colormap that this widget will use.

cursor	       The cursor to use when the mouse pointer is
	       over the Paned widget, but not in any of its
	       children (children may also inherit this cur-
	       sor).  It should be noted that the internal
	       borders are actually part of the Paned wid-
	       get, not the children.

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

gripCursor     The cursor to use when the grips are not
	       active.	The default value is vertical-
	       GripCursor or horizontalGripCursor depending
	       on the orientation of the Paned widget.

gripIndent     The amount of space left between the right
	       (or bottom) edge of the Paned widget and all
	       the grips.

gripTranslation
	       Translation table that will be applied to all
	       grips.

height
width	       The height and width of this widget in pix-
	       els.

horizontalBetweenCursor
verticalBetweenCursor
	       The cursor to be used for the grip when
	       changing the boundary between two panes.
	       These resources allow the cursors to be dif-
	       ferent depending on the orientation of the
	       Paned widget.

horizontalGripCursor
verticalGripCursor
	       The cursor to be used for the grips when they
	       are not active. These resources allow the
	       cursors to be different depending on the ori-
	       entation of the Paned widget.

internalBorderColor
	       A pixel value which indexes the widget's col-
	       ormap to derive the internal border color of
	       the widget's window.  The class name of this



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	       resource allows Paned*BorderColor: blue to
	       set the internal border color for the Paned
	       widget.	An optimization is invoked if inter-
	       nalBorderColor and background are the same,
	       and the internal borders are not drawn.
	       internalBorderWidth is still left between the
	       panes, however.

internalBorderWidth
	       The width of the internal borders.  This is
	       the amount of space left between the panes.
	       The class name of this resource allows
	       Paned*BorderWidth: 3 to set the internal bor-
	       der width for the Paned widget.

leftCursor
rightCursor    The cursor used to indicate which is the
	       important pane to resize when the Paned wid-
	       get is oriented horizontally.

lowerCursor
upperCursor    The cursor used to indicate which is the
	       important pane to resize when the Paned wid-
	       get is oriented vertically.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

numChildren    The number of children in this composite wid-
	       get.  This is not the same as the number of
	       panes, since this also contains a grip for
	       some of the panes, use XawPanedGetNumSub to
	       retrieve the number of panes.

orientation    The orientation to stack the panes.  This
	       value can be either XtorientVertical or Xto-
	       rientHorizontal.  A converter is registered
	       for this resource that will convert the fol-
	       lowing strings: vertical and horizontal.

refigureMode   This resource allows pane layout to be sus-
	       pended.	If this value is False, then no lay-
	       out actions will be taken.  This may improve
	       efficiency when adding or removing more than
	       one pane from the Paned widget.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive



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	       or sensitive is False.

translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

6.4.3.	Constraint Resources

Each child of the Paned widget may request special layout
resources be applied to it.  These constraint resources
allow the Paned widget's children to specify individual lay-
out requirements.


----------------------------------------------------------------------------------
Name		    Class		Type	     Notes   Default Value
----------------------------------------------------------------------------------
allowResize	    Boolean		Boolean 	     False
max		    Max 		Dimension	     Infinity
min		    Min 		Dimension	     Height of Grips
preferredPaneSize   PreferredPaneSize	Dimension	     ask child
resizeToPreferred   Boolean		Boolean 	     False
showGrip	    ShowGrip		Boolean 	     True
skipAdjust	    Boolean		Boolean 	     False
----------------------------------------------------------------------------------


allowResize    If this value is False the the Paned widget
	       will disallow all geometry requests from this
	       child.

max
min	       The absolute maximum or minimum size for this
	       pane.  These values will never be overridden
	       by the Paned widget.  This may cause some
	       panes to be pushed off the bottom (or right)
	       edge of the paned widget.

preferredPaneSize
	       Normally the paned widget makes a QueryGeome-
	       try call on a child to determine the pre-
	       ferred size of the child's pane.  There are
	       times when the application programmer or the
	       user has a better idea of the preferred size
	       of a pane.  Setting this resource causes the
	       value passed to be interpreted as the pre-
	       ferred size, in pixels, of this pane.

resizeToPreferred
	       Determines whether or not to resize each pane
	       to its preferred size when the Paned widget



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	       is resized.  See Layout Semantics for
	       details.

showGrip       If True then a grip will be shown for this
	       pane.  The grip associated with a pane is
	       either below or to the right of the pane.  No
	       grip is ever shown for the last pane.

skipAdjust     This resource is used to determine which pane
	       is forced to be resized.  Setting this value
	       to True makes this pane less likely to be
	       forced to be resized.  See Layout Semantics
	       for details.

6.4.4.	Layout Semantics

In order to make effective use of the Paned widget it is
helpful to know the rules it uses to determine which child
will be resized in any given situation.  There are three
rules used to determine which child is resized.  While these
rules are always the same, the panes that are searched can
change depending upon what caused the relayout.


Layout Rules

1    Do not let a pane grow larger than its max or smaller
     than its min.

2    Do not adjust panes with skipAdjust set.

3    Do not adjust panes away from their preferred size,
     although moving one closer to its preferred size is
     fine.

When searching the children the Paned widget looks for panes
that satisfy all the rules, and if unsuccessful then it
eliminates rule 3 and then 2.  Rule 1 is always enforced.

If the relayout is due to a resize or change in management
then the panes are searched from bottom to top.  If the
relayout is due to grip movement then they are searched from
the grip selected in the direction opposite the pane
selected.

6.4.4.1.  Resizing Panes from a Grip Action

The pane above the grip is resized by invoking the Gri-
pAction with UpLeftPane specified.  The panes below the grip
are each checked against all rules, then rules 2 and 1 and
finally against rule 1 only.  No pane above the chosen pane
will ever be resized.





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The pane below the grip is resized by invoking the Gri-
pAction with LowRightPane specified.  The panes above the
grip are each checked in this case.  No pane below the cho-
sen pane will ever be resized.

Invoking GripAction with ThisBorderOnly specified just moves
the border between the panes.  No other panes are ever
resized.

6.4.4.2.  Resizing Panes after the Paned widget is resized.

When the Pane widget is resized it must determine a new size
for each pane.	There are two methods of doing this.  The
Paned widget can either give each pane its preferred size
and then resize the panes to fit, or it can use the current
sizes and then resize the panes to fit.  The resizeToPre-
ferred resource allows the application to tell the Paned
widget whether to query the child about its preferred size
(subject to the the preferredPaneSize) or to use the current
size when refiguring the pane locations after the pane has
been resized.

There is one special case.  All panes assume they should
resize to their preferred size until the Paned widget
becomes visible to the user.

6.4.4.3.  Managing Children and Geometry Management

The Paned widget always resizes its children to their pre-
ferred sizes when a new child is managed, or a geometry man-
agement request is honored.  The Paned widget will first
attempt to resize itself to contain its panes exactly.	If
this is not possible then it will hunt through the children,
from bottom to top (right to left), for a pane to resize.

6.4.4.4.  Special Considerations

When a user resizes a pane with the grips, the Paned widget
assumes that this new size is the preferred size of the
pane.

6.4.5.	Grip Translations

The Paned widget has no action routines of its own, as all
actions are handled through the grips.	The grips are each
assigned a default Translation table.



     <Btn1Down>:      GripAction(Start, UpLeftPane)
     <Btn2Down>:      GripAction(Start, ThisBorderOnly)
     <Btn3Down>:      GripAction(Start, LowRightPane)
     <Btn1Motion>:    GripAction(Move, UpLeftPane)
     <Btn2Motion>:    GripAction(Move, ThisBorderOnly)



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     <Btn3Motion>:    GripAction(Move, LowRightPane)
     Any<BtnUp>:      GripAction(Commit)



The Paned widget interprets the GripAction as taking two
arguments.  The first argument may be any of the following:

Start	  Sets up the Paned widget for resizing and changes
	  the cursor of the grip.  The second argument
	  determines which pane will be resized, and can
	  take on any of the three values shown above.

Move	  The internal borders are drawn over the current
	  pane locations to animate where the borders would
	  actually be placed if you were to move this border
	  as shown.  The second argument must match the sec-
	  ond argument that was passed to the Start action,
	  that began this process.  If these arguments are
	  not passed, the behavior is undefined.

Commit	  This argument causes the Paned widget to commit
	  the changes selected by the previously started
	  action.  The cursor is changed back to the grip's
	  inactive cursor.  No second argument is needed in
	  this case.

6.4.6.	Convenience Routines

To enable or disable a child's request for pane resizing,
use XawPanedAllowResize:

void XawPanedAllowResize(w, allow_resize)
     Widget w;
     Boolean allow_resize;


w	  Specifies the child pane.

allow_resize
	  Specifies whether or not resizing requests for
	  this child will be granted by the Paned widget.

If allow_resize is True, the Paned widget allows geometry
requests from the child to change the pane's height. If
allow_resize is False, the Paned widget ignores geometry
requests from the child to change the pane's height. The
default state is True before the Pane is realized and False
after it is realized.  This procedure is equivalent to
changing the allowResize constraint resource for the child.


To change the minimum and maximum height settings for a
pane, use XawPanedSetMinMax:



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void XawPanedSetMinMax(w, min, max)
     Widget w;
     int min, max;


w	  Specifies the child pane.

min	  Specifies the new minimum height of the child,
	  expressed in pixels.

max	  Specifies new maximum height of the child,
	  expressed in pixels.

This procedure is equivalent to setting the min and max con-
straint resources for the child.


To retrieve the minimum and maximum height settings for a
pane, use XawPanedGetMinMax:

void XawPanedGetMinMax(w, min_return, max_return)
     Widget w;
     int *min_return, *max_return;


w	  Specifies the child pane.

min_return
	  Returns the minimum height of the child, expressed
	  in pixels.

max_return
	  Returns the maximum height of the child, expressed
	  in pixels.

This procedure is equivalent to getting the min and max
resources for this child child.


To enable or disable automatic recalculation of pane sizes
and positions, use XawPanedSetRefigureMode:

void XawPanedSetRefigureMode(w, mode)
     Widget w;
     Boolean mode;


w	  Specifies the Paned widget.

mode	  Specifies whether the layout of the Paned widget
	  is enabled (True) or disabled (False).

When making several changes to the children of a Paned wid-
get after the Paned has been realized, it is a good idea to



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disable relayout until after all changes have been made.


To retrieve the number of panes in a paned widget use Xaw-
PanedGetNumSub:

int XawPanedGetNumSub(w)
     Widget w;


w	  Specifies the Paned widget.

This function returns the number of panes in the Paned wid-
get.  This is not the same as the number of children, since
the grips are also children of the Paned widget.

6.5.  Porthole Widget



Application Header file<X11/Xaw/Porthole.h>
Class Header file   <X11/Xaw/PortholeP.h>
Class		    portholeWidgetClass
Class Name	    Porthole
Superclass	    Composite



The Porthole widget provides geometry management of a list
of arbitrary widgets, only one of which may be managed at
any particular time.  The managed child widget is reparented
within the porthole and is moved around by the application
(typically under the control of a Panner widget).

6.5.1.	Resources

When creating a Porthole widget instance, the following
resources are retrieved from the argument list or from the
resource database:


----------------------------------------------------------------------------
Name		 Class		  Type		  NotesDefault Value
----------------------------------------------------------------------------
accelerators	 Accelerators	  AcceleratorTable     NULL
ancestorSensitiveAncestorSensitiveBoolean	  D    True
background	 Background	  Pixel 	       XtDefaultBackground
backgroundPixmap Pixmap 	  Pixmap	       XtUnspecifiedPixmap
borderColor	 BorderColor	  Pixel 	       XtDefaultForeground
borderPixmap	 Pixmap 	  Pixmap	       XtUnspecifiedPixmap
borderWidth	 BorderWidth	  Dimension	       1
children	 ReadOnly	  WidgetList	  R    NULL
colormap	 Colormap	  Colormap	       Parent's Colormap




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----------------------------------------------------------------------------
Name		 Class		  Type		  NotesDefault Value
----------------------------------------------------------------------------
depth		 Depth		  int		  C    Parent's Depth
destroyCallback  Callback	  XtCallbackList       NULL
height		 Height 	  Dimension	  A    see Layout Semantics
mappedWhenManagedMappedWhenManagedBoolean	       True
numChildren	 ReadOnly	  Cardinal	  R    0
reportCallback	 ReportCallback   Callback	       NULL
screen		 Screen 	  Screen	  R    Parent's Screen
sensitive	 Sensitive	  Boolean	       True
translations	 Translations	  TranslationTable     NULL
width		 Width		  Dimension	  A    see Layout Semantics
x		 Position	  Position	       0
y		 Position	  Position	       0
----------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.




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children       A list of all this composite widget's current
	       children.

colormap       The colormap that this widget will use.

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

height
width	       The height and width of this widget in pix-
	       els.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

numChildren    The number of children in this composite wid-
	       get.

reportCallback A list of functions to invoke whenever the
	       managed child widget changes size or posi-
	       tion.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

6.5.2.	Layout Semantics

The Porthole widget allows its managed child to request any
size that is as large or larger than the Porthole itself and
any location so long as the child still obscures all of the
Porthole.  This widget typically is used with a Panner wid-
get.

6.5.3.	Porthole Callbacks

The functions registered on the reportCallback list are
invoked whenever the managed child changes size or position:



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void ReportProc(porthole, client_data, report)
     Widget porthole;
     XtPointer client_data;
     XtPointer report;	  /* (XawPannerReport *) */


porthole  Specifies the Porthole widget.

client_data
	  Specifies the client data.

report	  Specifies a pointer to an XawPannerReport struc-
	  ture containing the location and size of the
	  slider and the size of the canvas.


6.6.  Tree Widget



Application Header file<X11/Xaw/Tree.h>
Class Header file   <X11/Xaw/TreeP.h>
Class		    treeWidgetClass
Class Name	    Tree
Superclass	    Constraint



The Tree widget provides geometry management of arbitrary
widgets arranged in a directed, acyclic graph (i.e., a
tree).	The hierarchy is constructed by attaching a con-
straint resource called treeParent to each widget indicating
which other node in the tree should be treated as the wid-
get's superior.  The structure of the tree is shown by lay-
ing out the nodes in the standard format for tree diagrams
with lines drawn connecting each node with its children.

The Tree sizes itself according to the needs of its children
and is not intended to be resized by its parent.  Instead,
it should be placed inside another composite widget (such as
the Porthole or Viewport) that can be used to scroll around
in the tree.

6.6.1.	Resources

When creating a Tree widget instance, the following
resources are retrieved from the argument list or from the
resource database:









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----------------------------------------------------------------------------
Name		 Class		  Type		  NotesDefault Value
----------------------------------------------------------------------------
accelerators	 Accelerators	  AcceleratorTable     NULL
ancestorSensitiveAncestorSensitiveBoolean	  D    True
autoReconfigure  AutoReconfigure  Boolean	       False
background	 Background	  Pixel 	       XtDefaultBackground
backgroundPixmap Pixmap 	  Pixmap	       XtUnspecifiedPixmap
borderColor	 BorderColor	  Pixel 	       XtDefaultForeground
borderPixmap	 Pixmap 	  Pixmap	       XtUnspecifiedPixmap
borderWidth	 BorderWidth	  Dimension	       1
children	 ReadOnly	  WidgetList	  R    NULL
colormap	 Colormap	  Colormap	       Parent's Colormap
depth		 Depth		  int		  C    Parent's Depth
destroyCallback  Callback	  XtCallbackList       NULL
foreground	 Foreground	  Pixel 	       XtDefaultForeground
gravity 	 Gravity	  XtGravity	       WestGravity
height		 Height 	  Dimension	  A    see Layout Semantics
hSpace		 HSpace 	  Dimension	       4
lineWidth	 LineWidth	  Dimension	       0
mappedWhenManagedMappedWhenManagedBoolean	       True
numChildren	 ReadOnly	  Cardinal	  R    0
screen		 Screen 	  Screen	  R    Parent's Screen
sensitive	 Sensitive	  Boolean	       True
vSpace		 VSpace 	  Dimension	       4
translations	 Translations	  TranslationTable     NULL
width		 Width		  Dimension	  A    see Layout Semantics
x		 Position	  Position	       0
y		 Position	  Position	       0
----------------------------------------------------------------------------


autoReconfigure
	       Whether or not to layout the tree every time
	       a node is added or removed.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.

borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap



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	       specified will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

children       A list of all this composite widget's current
	       children.

colormap       The colormap that this widget will use.

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

foreground     A pixel value which indexes the widget's col-
	       ormap to derive the foreground color of the
	       widget's window.  This color is also used to
	       render all 1's in a bitmap one plane deep.

gravity        Specifies the side of the widget from which
	       the tree should grow.  Valid values include
	       WestGravity, NorthGravity, EastGravity, and
	       SouthGravity.  A converter is registered for
	       this resource that will convert the following
	       strings:  the legal values.

height
width	       The height and width of this widget in pix-
	       els.

hSpace
vSpace	       The amount of space, in pixels, to leave
	       between the children.  This resource speci-
	       fies the amount of space left between the
	       outermost children and the edge of the box.

lineWidth      The width of the lines from nodes that do not
	       have a treeGC constraint resource to their
	       children.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

numChildren    The number of children in this composite wid-
	       get.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.





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sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.

translations   The event bindings associated with this wid-
	       get.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

6.6.2.	Constraint Resources

Each child of the Tree widget must specify its superior node
in the tree.  In addition, it may specify a GC to use when
drawing a line between it and its inferior nodes.

--------------------------------------------------------------------
Name	     Class	  Type	       Notes   Default Value
--------------------------------------------------------------------
treeGC	     TreeGC	  GC		       NULL
treeParent   TreeParent   Widget	       NULL
--------------------------------------------------------------------


treeGC	       This specifies the GC to use when drawing
	       lines between this widget and its inferiors
	       in the tree.  If this resource is not speci-
	       fied, the Tree's foreground and lineWidth
	       will be used.

treeParent     This specifies the superior node in the tree
	       for this widget.  The default is for the node
	       to have no superior (and to therefore be at
	       the top of the tree).

6.6.3.	Layout Semantics

Each time a child is managed or unmanaged, the Tree widget
will attempt to reposition the remaining children to fix the
shape of the tree if the autoReconfigure resource is set.
Children at the top (most superior) of the tree are drawn at
the side specified by the gravity resource.

After positioning all children, the Tree widget attempts to
shrink its own size to the minimum dimensions required for
the layout.

6.6.4.	Convenience Routines

The most efficient way to layout a tree is to set autoRecon-
figure to False and then use the XawTreeForceLayout routine
to arrange the children.



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void XawTreeForceLayout(w)
     Widget w;


w	  Specifies the Tree widget.

6.7.  Viewport Widget



Application Header file<X11/Xaw/Viewport.h>
Class Header file   <X11/Xaw/ViewportP.h>
Class		    viewportWidgetClass
Class Name	    Viewport
Superclass	    Form



The Viewport widget consists of a frame window, one or two
Scrollbars, and an inner window.  The size of the frame win-
dow is determined by the viewing size of the data that is to
be displayed and the dimensions to which the Viewport is
created.  The inner window is the full size of the data that
is to be displayed and is clipped by the frame window.	The
Viewport widget controls the scrolling of the data directly.
No application callbacks are required for scrolling.

When the geometry of the frame window is equal in size to
the inner window, or when the data does not require
scrolling, the Viewport widget automatically removes any
scrollbars.  The forceBars option causes the Viewport widget
to display all scrollbars permanently.

6.7.1.	Resources

When creating a Viewport widget instance, the following
resources are retrieved from the argument list or the
resource database:


----------------------------------------------------------------------------
Name		 Class		  Type		  NotesDefault Value
----------------------------------------------------------------------------
accelerators	 Accelerators	  AcceleratorTable     NULL
allowHoriz	 Boolean	  Boolean	       False
allowVert	 Boolean	  Boolean	       False
ancestorSensitiveAncestorSensitiveBoolean	  D    True
background	 Background	  Pixel 	       XtDefaultBackground
backgroundPixmap Pixmap 	  Pixmap	       XtUnspecifiedPixmap
borderColor	 BorderColor	  Pixel 	       XtDefaultForeground
borderPixmap	 Pixmap 	  Pixmap	       XtUnspecifiedPixmap
borderWidth	 BorderWidth	  Dimension	       1
children	 ReadOnly	  WidgetList	  R    NULL




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----------------------------------------------------------------------------
Name		 Class		  Type		  NotesDefault Value
----------------------------------------------------------------------------
colormap	 Colormap	  Colormap	       Parent's Colormap
depth		 Depth		  int		  C    Parent's Depth
destroyCallback  Callback	  XtCallbackList       NULL
forceBars	 Boolean	  Boolean	       False
height		 Height 	  Dimension	       height of the child
mappedWhenManagedMappedWhenManagedBoolean	       True
numChildren	 ReadOnly	  Cardinal	  R    0
reportCallback	 ReportCallback   XtCallbackList       NULL
screen		 Screen 	  Screen	  R    Parent's Screen
sensitive	 Sensitive	  Boolean	       True
translations	 Translations	  TranslationTable     NULL
useBottom	 Boolean	  Boolean	       False
useRight	 Boolean	  Boolean	       False
width		 Width		  Dimension	       width of the child
x		 Position	  Position	       0
y		 Position	  Position	       0
----------------------------------------------------------------------------


accelerators   A list of event to action bindings to be exe-
	       cuted by this widget, even though the event
	       occurred in another widget.  (See the X
	       Toolkit Intrinsics -- C Language Interface
	       for details).

allowHoriz
allowVert      If these resources are False then the View-
	       port will never create a scrollbar in this
	       direction.  If it is True then the scrollbar
	       will only appear when it is needed, unless
	       forceBars is True.

ancestorSensitive
	       The sensitivity state of the ancestors of
	       this widget.  A widget is insensitive if
	       either it or any of its ancestors is insensi-
	       tive.  This resource should not be changed
	       with XtSetValues, although it may be queried.

background     A pixel value which indexes the widget's col-
	       ormap to derive the background color of the
	       widget's window.

backgroundPixmap
	       The background pixmap of this widget's win-
	       dow.  If this resource is set to anything
	       other than XtUnspecifiedPixmap, the pixmap
	       specified will be used instead of the back-
	       ground color.





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borderColor    A pixel value which indexes the widget's col-
	       ormap to derive the border color of the wid-
	       get's window.

borderPixmap   The border pixmap of this widget's window.
	       If this resource is set to anything other
	       than XtUnspecifiedPixmap, the pixmap speci-
	       fied will be used instead of the border
	       color.

borderWidth    The width of this widget's window border.

children       A list of all this composite widget's current
	       children.

colormap       The colormap that this widget will use.

depth	       The depth of this widget's window.

destroyCallback
	       All functions on this list are called when
	       this widget is destroyed.

forceBars      When True the scrollbars that have been
	       allowed will always be visible on the screen.
	       If False the scrollbars will be visible only
	       when the inner window is larger than the
	       frame.

height
width	       The height and width of this widget in pix-
	       els.

mappedWhenManaged
	       If this resource is True, then the widget's
	       window will automatically be mapped by the
	       Toolkit when it is realized and managed.

numChildren    The number of children in this composite wid-
	       get.

reportCallback These callbacks will be executed whenever the
	       Viewport adjusts the viewed area of the
	       child.  The call_data parameter is a pointer
	       to an XawPannerReport structure.

screen	       The screen on which this widget is displayed.
	       This is not a settable resource.

sensitive      Whether or not the toolkit should pass user
	       events to this widget.  The widget will not
	       get input events if either ancestorSensitive
	       or sensitive is False.




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translations   The event bindings associated with this wid-
	       get.

useBottom
useRight       By default the scrollbars appear on the left
	       and top of the screen.  These resources allow
	       the vertical scrollbar to be placed on the
	       right edge of the Viewport, and the horizon-
	       tal scrollbar on the bottom edge of the View-
	       port.

x
y	       The location of the upper left outside corner
	       of this widget in its parent.

6.7.2.	Layout Semantics

The Viewport widget manages a single child widget.  When the
size of the child is larger than the size of the Viewport,
the user can interactively move the child within the View-
port by repositioning the scrollbars.

The default size of the Viewport before it is realized is
the width and/or height of the child.  After it is realized,
the Viewport will allow its child to grow vertically or hor-
izontally if allowVert or allowHoriz are set, respectively.
If the corresponding vertical or horizontal scrollbar is not
enabled, the Viewport will propagate the geometry request to
its own parent and the child will be allowed to change size
only if the Viewport's parent allows it.  Regardless of
whether or not scrollbars are enabled in the corresponding
direction, if the child requests a new size smaller than the
Viewport size, the change will be allowed only if the parent
of the Viewport allows the Viewport to shrink to the appro-
priate dimension.

The scrollbar children of the Viewport are named horizontal
and vertical.  By using these names the programmer can spec-
ify resources for the individual scrollbars.  XtSetValues
can be used to modify the resources dynamically once the
widget ID has been obtained with XtNameToWidget.

			    Note

     Although the Viewport is a Subclass of the Form,
     no resources for the Form may be supplied for any
     of the children of the Viewport.  These con-
     straints are managed internally and are not meant
     for public consumption.








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			 Chapter 7

	     Creating New Widgets (Subclassing)

		  Written By: Ralph Swick




Although the task of creating a new widget may at first
appear a little daunting, there is a basic simple pattern
that all widgets follow.  The Athena Widget library contains
a special widget called the Template widget that is intended
to assist the novice widget programmer in writing a custom
widget.

Reasons for wishing to write a custom widget include:

o  Providing a graphical interface not currently supported
   by any existing widget set.

o  Convenient access to resource management procedures to
   obtain fonts, colors, etc., even if user customization is
   not desired.

o  Convenient access to user input dispatch and translation
   management procedures.

o  Access to callback mechanism for building higher-level
   application libraries.

o  Customizing the interface or behavior of an existing wid-
   get to suit a special application need.

o  Desire to allow user customization of resources such as
   fonts, colors, etc., or to allow convenient re-binding of
   keys and buttons to internal functions.

o  Converting a non-Toolkit application to use the Toolkit.

In each of these cases, the operation needed to create a new
widget is to "subclass" an existing one.  If the desired
semantics of the new widget are similar to an existing one,
then the implementation of the existing widget should be
examined to see how much work would be required to create a
subclass that will then be able to share the existing class
methods.  Much time will be saved in writing the new widget
if an existing widget class Expose, Resize and/or Geometry-
Manager method can be used by the subclass.

Note that some trivial uses of a ``bare-bones'' widget may
be achieved by simply creating an instance of the Core



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widget.  The class variable to use when creating a Core wid-
get is widgetClass.  The geometry of the Core widget is
determined entirely by the parent widget.

It is very often the case than an application will have a
special need for a certain set of functions and that many
copies of these functions will be needed.  For example, when
converting an older application to use the Toolkit, it may
be desirable to have a "Window Widget" class that might have
the following semantics:

o  Allocate 2 drawing colors in addition to a background
   color.

o  Allocate a text font.

o  Execute an application-supplied function to handle expo-
   sure events.

o  Execute an application-supplied function to handle user
   input events.

It is obvious that a completely general-purpose WindowWid-
getClass could be constructed that would export all class
methods as callbacks lists, but such a widget would be very
large and would have to choose some arbitrary number of
resources such as colors to allocate.  An application that
used many instances of the general-purpose widget would
therefore un-necessarily waste many resources.


In this section, an outline will be given of the procedure
to follow to construct a special-purpose widget to address
the items listed above.  The reader should refer to the
appropriate sections of the X Toolkit Intrinsics -- C Lan-
guage Interface for complete details of the material out-
lined here.  Section 1.4 of the Intrinsics should be read in
conjunction with this section.

All Athena widgets have three separate files associated with
them:


o  A "public" header file containing declarations needed by
   applications programmers

o  A "private" header file containing additional declara-
   tions needed by the widget and any subclasses

o  A source code file containing the implementation of the
   widget

This separation of functions into three files is suggested
for all widgets, but nothing in the Toolkit actually



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requires this format.  In particular, a private widget cre-
ated for a single application may easily combine the "pub-
lic" and "private" header files into a single file, or merge
the contents into another application header file.  Simi-
larly, the widget implementation can be merged into other
application code.


In the following example, the public header file
<X11/Xaw/Template.h>, the private header file
<X11/Xaw/TemplateP.h> and the source code file
<X11/Xaw/Template.c> will be modified to produce the "Win-
dowWidget" described above.  In each case, the files have
been designed so that a global string replacement of ``Tem-
plate'' and ``template'' with the name of your new widget,
using the appropriate case, can be done.

7.1.  Public Header File

The public header file contains declarations that will be
required by any application module that needs to refer to
the widget; whether to create an instance of the class, to
perform an XtSetValues operation, or to call a public rou-
tine implemented by the widget class.

The contents of the Template public header file,
<X11/Xaw/Template.h>, are:


  /* XConsortium: Template.h,v 1.2 88/10/25 17:22:09 swick Exp $ */
  /* Copyright (c) X Consortium 1987, 1988 */

  #ifndef _Template_h
  #define _Template_h

  /****************************************************************
   *
   * Template widget
   *
   ****************************************************************/

  /* Resources:

   Name 	Class	     RepType Default Value
   ---- 		  -----      --------------------
   background	Background	     PixelXtDefaultBackground
   border	BorderColor	     PixelXtDefaultForeground
   borderWidth	BorderWidth	     Dimension1
   destroyCallback	  Callback   PointerNULL
   height	Height	     Dimension0
   mappedWhenManaged	  MappedWhenManagedBooleanTrue
   sensitive	Sensitive    Boolean True
   width	Width	     Dimension0
   x			  Position   Position0



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   y			  Position   Position0

  */

  /* define any special resource names here that are not in <X11/StringDefs.h> */

  #define XtNtemplateResource "templateResource"

  #define XtCTemplateResource "TemplateResource"

  /* declare specific TemplateWidget class and instance datatypes */

  typedef struct _TemplateClassRec*  TemplateWidgetClass;
  typedef struct _TemplateRec*	     TemplateWidget;

  /* declare the class constant */

  extern WidgetClass templateWidgetClass;

  #endif /* _Template_h */



You will notice that most of this file is documentation.
The crucial parts are the last 8 lines where macros for any
private resource names and classes are defined and where the
widget class datatypes and class record pointer are
declared.

For the "WindowWidget", we want 2 drawing colors, a callback
list for user input and an exposeCallback callback list, and
we will declare three convenience procedures, so we need to
add




  /* Resources:
    ...
   callback	Callback  Callback   NULL
   drawingColor1	  Color      PixelXtDefaultForeground
   drawingColor2	  Color      PixelXtDefaultForeground
   exposeCallback	  Callback   CallbackNULL
   font 		  Font	     XFontStruct*XtDefaultFont
    ...
   */

  #define XtNdrawingColor1 "drawingColor1"
  #define XtNdrawingColor2 "drawingColor2"
  #define XtNexposeCallback "exposeCallback"

  extern Pixel WindowColor1(/* Widget */);
  extern Pixel WindowColor2(/* Widget */);
  extern Font  WindowFont(/* Widget */);



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Note that we have chosen to call the input callback list by
the generic name, callback, rather than a specific name.  If
widgets that define a single user-input action all choose
the same resource name then there is greater possibility for
an application to switch between widgets of different types.

7.2.  Private Header File

The private header file contains the complete declaration of
the class and instance structures for the widget and any
additional private data that will be required by anticipated
subclasses of the widget.  Information in the private header
file is normally hidden from the application and is designed
to be accessed only through other public procedures; e.g.
XtSetValues.

The contents of the Template private header file,
<X11/Xaw/TemplateP.h>, are:


  /* XConsortium: TemplateP.h,v 1.2 88/10/25 17:31:47 swick Exp $ */

  /* Copyright (c) X Consortium 1987, 1988
   */

  #ifndef _TemplateP_h
  #define _TemplateP_h

  #include <X11/Xaw/Template.h>
  /* include superclass private header file */
  #include <X11/CoreP.h>

  /* define unique representation types not found in <X11/StringDefs.h> */

  #define XtRTemplateResource "TemplateResource"

  typedef struct {
    int empty;
  } TemplateClassPart;

  typedef struct _TemplateClassRec {
    CoreClassPart	  core_class;
    TemplateClassPart	  template_class;
  } TemplateClassRec;

  extern TemplateClassRec templateClassRec;

  typedef struct {
    /* resources */
    char* resource;
    /* private state */
  } TemplatePart;

  typedef struct _TemplateRec {



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    CorePart	core;
    TemplatePart	  template;
  } TemplateRec;

  #endif /* _TemplateP_h */



The private header file includes the private header file of
its superclass, thereby exposing the entire internal struc-
ture of the widget.  It may not always be advantageous to do
this; your own project development style will dictate the
appropriate level of detail to expose in each module.

The "WindowWidget" needs to declare two fields in its
instance structure to hold the drawing colors, a resource
field for the font and a field for the expose and user input
callback lists:


  typedef struct {
    /* resources */
    Pixel color_1;
    Pixel color_2;
    XFontStruct* font;
    XtCallbackList expose_callback;
    XtCallbackList input_callback;
    /* private state */
    /* (none) */
  } WindowPart;


7.3.  Widget Source File

The source code file implements the widget class itself.
The unique part of this file is the declaration and initial-
ization of the widget class record structure and the decla-
ration of all resources and action routines added by the
widget class.

The contents of the Template implementation file,
<X11/Xaw/Template.c>, are:


  /* XConsortium: Template.c,v 1.2 88/10/25 17:40:25 swick Exp $ */

  /* Copyright (c) X Consortium 1987, 1988
   */

  #include <X11/IntrinsicP.h>
  #include <X11/StringDefs.h>
  #include "TemplateP.h"

  static XtResource resources[] = {



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  #define offset(field) XtOffsetOf(TemplateRec, template.field)
    /* {name, class, type, size, offset, default_type, default_addr}, */
      { XtNtemplateResource, XtCTemplateResource, XtRTemplateResource,
      sizeof(char*), offset(resource), XtRString, (XtPointer) "default" },
  #undef offset
  };

  static void TemplateAction(/* Widget, XEvent*, String*, Cardinal* */);

  static XtActionsRec actions[] =
  {
    /* {name,	procedure}, */
    {"template",	  TemplateAction},
  };

  static char translations[] =
  " <Key>:	template() \n\
  ";

  TemplateClassRec templateClassRec = {
    { /* core fields */
    /* superclass	  */ (WidgetClass) &widgetClassRec,
    /* class_name	  */ "Template",
    /* widget_size	  */ sizeof(TemplateRec),
    /* class_initialize   */ NULL,
    /* class_part_initialize */      NULL,
    /* class_inited	  */ FALSE,
    /* initialize	  */ NULL,
    /* initialize_hook	  */ NULL,
    /* realize	*/	  XtInheritRealize,
    /* actions	*/	  actions,
    /* num_actions	  */ XtNumber(actions),
    /* resources	  */ resources,
    /* num_resources	  */ XtNumber(resources),
    /* xrm_class	  */ NULLQUARK,
    /* compress_motion	  */ TRUE,
    /* compress_exposure  */ TRUE,
    /* compress_enterleave */	     TRUE,
    /* visible_interest   */ FALSE,
    /* destroy	*/	  NULL,
    /* resize	*/	  NULL,
    /* expose	*/	  NULL,
    /* set_values	  */ NULL,
    /* set_values_hook	  */ NULL,
    /* set_values_almost  */ XtInheritSetValuesAlmost,
    /* get_values_hook	  */ NULL,
    /* accept_focus	  */ NULL,
    /* version	*/	  XtVersion,
    /* callback_private   */ NULL,
    /* tm_table */	  translations,
    /* query_geometry	  */ XtInheritQueryGeometry,
    /* display_accelerator   */      XtInheritDisplayAccelerator,
    /* extension	  */ NULL
    },



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Athena Widget Set			    X11, Release 6.4


    { /* template fields */
    /* empty	*/	  0
    }
  };

  WidgetClass templateWidgetClass = (WidgetClass)&templateClassRec;


The resource list for the "WindowWidget" might look like the
following:


  static XtResource resources[] = {
  #define offset(field) XtOffsetOf(WindowWidgetRec, window.field)
    /* {name, class, type, size, offset, default_type, default_addr}, */
    { XtNdrawingColor1, XtCColor, XtRPixel, sizeof(Pixel),
		  offset(color_1), XtRString, XtDefaultForeground },
    { XtNdrawingColor2, XtCColor, XtRPixel, sizeof(Pixel),
		  offset(color_2), XtRString, XtDefaultForeground },
    { XtNfont, XtCFont, XtRFontStruct, sizeof(XFontStruct*),
		  offset(font), XtRString, XtDefaultFont },
    { XtNexposeCallback, XtCCallback, XtRCallback, sizeof(XtCallbackList),
		  offset(expose_callback), XtRCallback, NULL },
    { XtNcallback, XtCCallback, XtRCallback, sizeof(XtCallbackList),
		  offset(input_callback), XtRCallback, NULL },
  #undef offset
  };


The user input callback will be implemented by an action
procedure which passes the event pointer as call_data.	The
action procedure is declared as:


  /* ARGSUSED */
  static void InputAction(w, event, params, num_params)
    Widget w;
    XEvent *event;
    String *params;	     /* unused */
    Cardinal *num_params; /* unused */
  {
    XtCallCallbacks(w, XtNcallback, (XtPointer)event);
  }

  static XtActionsRec actions[] =
  {
    /* {name,	procedure}, */
    {"input",	InputAction},
  };


and the default input binding will be to execute the input
callbacks on KeyPress and ButtonPress:




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Athena Widget Set			    X11, Release 6.4


  static char translations[] =
  " <Key>:	input() \n\
    <BtnDown>:	input() \
  ";


In the class record declaration and initialization, the only
field that is different from the Template is the expose pro-
cedure:


  /* ARGSUSED */
  static void Redisplay(w, event, region)
    Widget w;
    XEvent *event;	  /* unused */
    Region region;
  {
    XtCallCallbacks(w, XtNexposeCallback, (XtPointer)region);
  }

  WindowClassRec windowClassRec = {

    ...

    /* expose	*/	  Redisplay,



The "WindowWidget" will also declare three public procedures
to return the drawing colors and the font id, saving the
application the effort of constructing an argument list for
a call to XtGetValues:



  Pixel WindowColor1(w)
    Widget w;
  {
    return ((WindowWidget)w)->window.color_1;
  }

  Pixel WindowColor2(w)
    Widget w;
  {
    return ((WindowWidget)w)->window.color_2;
  }

  Font WindowFont(w)
    Widget w;
  {
    return ((WindowWidget)w)->window.font->fid;
  }





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Athena Widget Set			    X11, Release 6.4


The "WindowWidget" is now complete.  The application can
retrieve the two drawing colors from the widget instance by
calling either XtGetValues, or the WindowColor functions.
The actual window created for the "WindowWidget" is avail-
able by calling the XtWindow function.




















































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		     Table of Contents


Acknowledgments  . . . . . . . . . . . . . . . . . . . .   v
Chapter 1 - Athena Widgets and The Intrinsics  . . . . .   1
     Introduction to the X Toolkit . . . . . . . . . . .   1
     Terminology . . . . . . . . . . . . . . . . . . . .   2
     Underlying Model  . . . . . . . . . . . . . . . . .   4
     Input Focus . . . . . . . . . . . . . . . . . . . .   8
Chapter 2 - Using Widgets  . . . . . . . . . . . . . . .   9
     Setting the Locale  . . . . . . . . . . . . . . . .   9
     Initializing the Toolkit  . . . . . . . . . . . . .  10
     Creating a Widget . . . . . . . . . . . . . . . . .  11
     Common Resources  . . . . . . . . . . . . . . . . .  12
     Resource Conversions  . . . . . . . . . . . . . . .  13
     Realizing a Widget  . . . . . . . . . . . . . . . .  14
     Processing Events . . . . . . . . . . . . . . . . .  15
     Standard Widget Manipulation Functions  . . . . . .  15
     Using the Client Callback Interface . . . . . . . .  18
     Programming Considerations  . . . . . . . . . . . .  20
     Example Programs  . . . . . . . . . . . . . . . . .  26
Chapter 3 - Simple Widgets . . . . . . . . . . . . . . .  27
     Command Widget  . . . . . . . . . . . . . . . . . .  28
     Grip Widget . . . . . . . . . . . . . . . . . . . .  34
     Label Widget  . . . . . . . . . . . . . . . . . . .  38
     List Widget . . . . . . . . . . . . . . . . . . . .  43
     Panner Widget . . . . . . . . . . . . . . . . . . .  50
     Repeater Widget . . . . . . . . . . . . . . . . . .  56
     Scrollbar Widget  . . . . . . . . . . . . . . . . .  62
     Simple Widget . . . . . . . . . . . . . . . . . . .  71
     StripChart Widget . . . . . . . . . . . . . . . . .  74
     Toggle Widget . . . . . . . . . . . . . . . . . . .  78
Chapter 4 - Menus  . . . . . . . . . . . . . . . . . . .  89
     Using the Menus . . . . . . . . . . . . . . . . . .  90
     SimpleMenu Widget . . . . . . . . . . . . . . . . .  90
     SmeBSB Object . . . . . . . . . . . . . . . . . . .  97
     SmeLine Object  . . . . . . . . . . . . . . . . . . 100
     Sme Object  . . . . . . . . . . . . . . . . . . . . 101
     MenuButton Widget . . . . . . . . . . . . . . . . . 103
Chapter 5 - Text Widgets.  . . . . . . . . . . . . . . . 111
     Text Widget for Users . . . . . . . . . . . . . . . 111
     Actions Supported by all Text Widgets . . . . . . . 116
     Default Translation Bindings  . . . . . . . . . . . 125
     Text Functions  . . . . . . . . . . . . . . . . . . 126
     AsciiText Widget  . . . . . . . . . . . . . . . . . 133
     AsciiSrc Object . . . . . . . . . . . . . . . . . . 140
     AsciiSink Object  . . . . . . . . . . . . . . . . . 145
     Customizing the Text Widget . . . . . . . . . . . . 147
     Text Widget . . . . . . . . . . . . . . . . . . . . 148
     TextSrc Object  . . . . . . . . . . . . . . . . . . 153
     TextSink Object . . . . . . . . . . . . . . . . . . 158
Chapter 6 - Composite and Constraint Widgets . . . . . . 166
     Box Widget  . . . . . . . . . . . . . . . . . . . . 167
     Dialog Widget . . . . . . . . . . . . . . . . . . . 170



			     iii








     Form Widget . . . . . . . . . . . . . . . . . . . . 177
     Paned Widget  . . . . . . . . . . . . . . . . . . . 182
     Porthole Widget . . . . . . . . . . . . . . . . . . 192
     Tree Widget . . . . . . . . . . . . . . . . . . . . 195
     Viewport Widget . . . . . . . . . . . . . . . . . . 199
Chapter 7 - Creating New Widgets (Subclassing) . . . . . 203
Index  . . . . . . . . . . . . . . . . . . . . . . . . . 213


















































			     iv


