YaST2 Developers Documentation: YCP UI Reference: Widgets


YCP UI Widget Reference

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Slider Numeric limited range input (optional widget)

Description

A horizontal slider with (numeric) input field that allows input of an integer value in a given range. The user can either drag the slider or simply enter a value in the input field.

Remember you can use `opt(`notify) in order to get instant response when the user changes the value - if this is desired.

Note: This is a "special" widget, i.e. not all UIs necessarily support it. Check for availability with HasSpecialWidget(`Slider) before using it.

Arguments

string label Explanatory label above the slider
integer minValue minimum value
integer maxValue maximum value
integer initialValue initial value

Special Properties

integer Value the numerical value
string Label the slider label

Sample Usage

if ( HasSpecialWidget(`Slider) {... `Slider("Percentage", 1, 100, 50)

Examples

Example 1: Slider1.ycp


UI(``{
    if ( ! HasSpecialWidget(`Slider) )
    {
	OpenDialog(
		   `VBox( 
			 `Label("Error: This UI doesn't support the Slider widget!"),
			 `PushButton(`opt(`default), "&OK")
			 )
		   );
	UserInput();
	CloseDialog();
	
	return;
    }
    
    OpenDialog(
	       `VBox(
		     `Slider( "Percentage", 0, 100, 50),
		     `PushButton(`opt(`default), "&OK")
		     )
	       );
    UserInput();
    CloseDialog();
})

Example 2: Slider2.ycp


// Advanced Slider + BarGraph example:
//
// Display a dialog with a bar graph for RGB color percentages
// and 3 sliders for the RGB percentage.
// Update the bar graph while the user adjusts the RGB values.
//
// Unfortunately the colors don't match any more in the BarGraph widget - they
// used to be red, blue and green. You need to use a bit of imagination
// here. ;-)

UI(``{
    // Check for availability of required widgets
    
    if ( ! HasSpecialWidget(`Slider) ||
	 ! HasSpecialWidget(`BarGraph ) )
    {
	OpenDialog(
		   `VBox( 
			 `Label("Error: This UI doesn't support the required special widgets!"),
			 `PushButton(`opt(`default), "&OK")
			 )
		   );
	UserInput();
	CloseDialog();
	
	return;
    }

    
    // Initialize RGB values
    
    integer red   = 128;
    integer blue  = 128;
    integer green = 128;


    // Create the dialog
    
    OpenDialog(
	       `VBox(
		     `HSpacing(50),	// force width
		     `BarGraph( `id(`graph),
				[ red, green, blue ],
				[ "Red\n%1", "Green\n%1", "Blue\n%1" ] ),
		     `Slider( `id(`red),   `opt(`notify), "Red",   0, 255, red   ),
		     `Slider( `id(`green), `opt(`notify), "Green", 0, 255, green ),
		     `Slider( `id(`blue),  `opt(`notify), "Blue",  0, 255, blue  ),
		     `PushButton(`id(`close), `opt(`default), "&Close")
		     )
	       );

    
    // Event processing loop - left only via the "close" button
    // or the window manager close button / function.
    do
    {
	any widget = UserInput();

	if ( widget == `red   ||	// any of the sliders?
	     widget == `blue  ||
	     widget == `green   )
	{
	    // Get all slider values
	    
	    red   = QueryWidget(`id(`red),   `Value );
	    green = QueryWidget(`id(`green), `Value );
	    blue  = QueryWidget(`id(`blue),  `Value );

	    
	    // Update bar graph
	    
	    ChangeWidget(`id(`graph), `Values, [ red, green, blue ] );
	}
    } while ( widget != `close &&	// the real "Close" button
	      widget != `cancel );	// the window manager close function/button
	
    CloseDialog();
})

Example 3: ColoredLabel3.ycp


/**
 * Advanced ColoredLabel example: A sample ColoredLabel widget and sliders
 * for both foreground and background colors.
 **/
UI(``{
    if ( ! HasSpecialWidget(`ColoredLabel) || ! HasSpecialWidget(`Slider) )
    {
	OpenDialog(
		   `VBox( 
			 `Label("Error: This UI doesn't support the required special widgets!"),
			 `PushButton(`opt(`default), "&OK")
			 )
		   );
	UserInput();
	CloseDialog();
	
	return;
    }

    define void sample( integer fg_red, integer fg_green, integer fg_blue,
			integer bg_red, integer bg_green, integer bg_blue ) ``{
	return `ColoredLabel( `opt(`hstretch),
			      "Use the sliders\nto change color",
			      `rgb( fg_red, fg_green, fg_blue ),
			      `rgb( bg_red, bg_green, bg_blue ),
			      30 );
    };
    
    OpenDialog(
	       `VBox(
		     `ReplacePoint(`id(`sample), sample( 200, 0, 0,
							 0, 0, 200) ),
		     `VSpacing(),
		     `HBox(
			   `Frame( "Foreground",
				   `VBox(
					 `Slider(`id(`fg_red  ),`opt(`notify), "&red",   0, 255, 200 ),
					 `Slider(`id(`fg_green),`opt(`notify), "&green", 0, 255,   0 ),
					 `Slider(`id(`fg_blue ),`opt(`notify), "&blue",  0, 255,   0 )
					 )
				   ),
			   `Frame( "Backround",
				   `VBox(
					 `Slider(`id(`bg_red  ), `opt(`notify), "r&ed",   0, 255,   0 ),
					 `Slider(`id(`bg_green), `opt(`notify), "gree&n", 0, 255,   0 ),
					 `Slider(`id(`bg_blue ), `opt(`notify), "b&lue",  0, 255, 200 )
					 )
				   )
			   ),
		     `VSpacing(),
		     `PushButton(`id(`close), "&Close")
		     )
	       );

    symbol widget = nil;

    do
    {
	widget = UserInput();

	if ( widget != `close )
	{
	    ReplaceWidget(`id(`sample),
			  sample( QueryWidget(`id(`fg_red  ), `Value ),
				  QueryWidget(`id(`fg_green), `Value ),
				  QueryWidget(`id(`fg_blue ), `Value ),
				  
				  QueryWidget(`id(`bg_red  ), `Value ),
				  QueryWidget(`id(`bg_green), `Value ),
				  QueryWidget(`id(`bg_blue ), `Value )
				  )
			  );

	}
	
    } while ( widget != `close );
    
    CloseDialog();
})

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YaST2 Developers Documentation: YCP UI Reference: Widgets

Generated Mon Oct 14 13:59:15 2002