Module com.googlecode.lanterna
Package com.googlecode.lanterna.gui2

Class GridLayout

  • All Implemented Interfaces:
    LayoutManager
    public class GridLayout
extends java.lang.Object
implements LayoutManager
    This emulates the behaviour of the GridLayout in SWT (as opposed to the one in AWT/Swing). I originally ported the SWT class itself but due to licensing concerns (the eclipse license is not compatible with LGPL) I was advised not to do that. This is a partial implementation and some of the semantics have changed, but in general it works the same way so the SWT documentation will generally match.

    You use the GridLayout by specifying a number of columns you want your grid to have and then when you add components, you assign LayoutData to these components using the different static methods in this class (createLayoutData(..)). You can set components to span both rows and columns, as well as defining how to distribute the available space.

    • Field Detail

      • numberOfColumns

        private final int numberOfColumns

      • horizontalSpacing

        private int horizontalSpacing

      • verticalSpacing

        private int verticalSpacing

      • topMarginSize

        private int topMarginSize

      • bottomMarginSize

        private int bottomMarginSize

      • leftMarginSize

        private int leftMarginSize

      • rightMarginSize

        private int rightMarginSize

      • changed

        private boolean changed

    • Constructor Detail

      • GridLayout

        public GridLayout​(int numberOfColumns)
        Creates a new GridLayout with the specified number of columns. Initially, this layout will have a horizontal spacing of 1 and vertical spacing of 0, with a left and right margin of 1.
        Parameters:
        numberOfColumns - Number of columns in this grid

    • Method Detail

      • createLayoutData

        public static LayoutData createLayoutData​(GridLayout.Alignment horizontalAlignment,
                                          GridLayout.Alignment verticalAlignment)
        Creates a layout data object for GridLayout:s that specify the horizontal and vertical alignment for the component in case the cell space is larger than the preferred size of the component
        Parameters:
        horizontalAlignment - Horizontal alignment strategy
        verticalAlignment - Vertical alignment strategy
        Returns:
        The layout data object containing the specified alignments

      • createLayoutData

        public static LayoutData createLayoutData​(GridLayout.Alignment horizontalAlignment,
                                          GridLayout.Alignment verticalAlignment,
                                          boolean grabExtraHorizontalSpace,
                                          boolean grabExtraVerticalSpace)
        Creates a layout data object for GridLayout:s that specify the horizontal and vertical alignment for the component in case the cell space is larger than the preferred size of the component. This method also has fields for indicating that the component would like to take more space if available to the container. For example, if the container is assigned is assigned an area of 50x15, but all the child components in the grid together only asks for 40x10, the remaining 10 columns and 5 rows will be empty. If just a single component asks for extra space horizontally and/or vertically, the grid will expand out to fill the entire area and the text space will be assigned to the component that asked for it.
        Parameters:
        horizontalAlignment - Horizontal alignment strategy
        verticalAlignment - Vertical alignment strategy
        grabExtraHorizontalSpace - If set to true, this component will ask to be assigned extra horizontal space if there is any to assign
        grabExtraVerticalSpace - If set to true, this component will ask to be assigned extra vertical space if there is any to assign
        Returns:
        The layout data object containing the specified alignments and size requirements

      • createLayoutData

        public static LayoutData createLayoutData​(GridLayout.Alignment horizontalAlignment,
                                          GridLayout.Alignment verticalAlignment,
                                          boolean grabExtraHorizontalSpace,
                                          boolean grabExtraVerticalSpace,
                                          int horizontalSpan,
                                          int verticalSpan)
        Creates a layout data object for GridLayout:s that specify the horizontal and vertical alignment for the component in case the cell space is larger than the preferred size of the component. This method also has fields for indicating that the component would like to take more space if available to the container. For example, if the container is assigned is assigned an area of 50x15, but all the child components in the grid together only asks for 40x10, the remaining 10 columns and 5 rows will be empty. If just a single component asks for extra space horizontally and/or vertically, the grid will expand out to fill the entire area and the text space will be assigned to the component that asked for it. It also puts in data on how many rows and/or columns the component should span.
        Parameters:
        horizontalAlignment - Horizontal alignment strategy
        verticalAlignment - Vertical alignment strategy
        grabExtraHorizontalSpace - If set to true, this component will ask to be assigned extra horizontal space if there is any to assign
        grabExtraVerticalSpace - If set to true, this component will ask to be assigned extra vertical space if there is any to assign
        horizontalSpan - How many "cells" this component wants to span horizontally
        verticalSpan - How many "cells" this component wants to span vertically
        Returns:
        The layout data object containing the specified alignments, size requirements and cell spanning

      • createHorizontallyFilledLayoutData

        public static LayoutData createHorizontallyFilledLayoutData()
        This is a shortcut method that will create a grid layout data object that will expand its cell as much as is can horizontally and make the component occupy the whole area horizontally and center it vertically, spanning 1 cell.
        Returns:
        Layout data object with the specified span and horizontally expanding as much as it can

      • createHorizontallyFilledLayoutData

        public static LayoutData createHorizontallyFilledLayoutData​(int horizontalSpan)
        This is a shortcut method that will create a grid layout data object that will expand its cell as much as is can horizontally and make the component occupy the whole area horizontally and center it vertically
        Parameters:
        horizontalSpan - How many cells to span horizontally
        Returns:
        Layout data object with the specified span and horizontally expanding as much as it can

      • createHorizontallyEndAlignedLayoutData

        public static LayoutData createHorizontallyEndAlignedLayoutData​(int horizontalSpan)
        This is a shortcut method that will create a grid layout data object that will expand its cell as much as is can vertically and make the component occupy the whole area vertically and center it horizontally
        Parameters:
        horizontalSpan - How many cells to span vertically
        Returns:
        Layout data object with the specified span and vertically expanding as much as it can

      • getHorizontalSpacing

        public int getHorizontalSpacing()
        Returns the horizontal spacing, i.e. the number of empty columns between each cell
        Returns:
        Horizontal spacing

      • setHorizontalSpacing

        public GridLayout setHorizontalSpacing​(int horizontalSpacing)
        Sets the horizontal spacing, i.e. the number of empty columns between each cell
        Parameters:
        horizontalSpacing - New horizontal spacing
        Returns:
        Itself

      • getVerticalSpacing

        public int getVerticalSpacing()
        Returns the vertical spacing, i.e. the number of empty columns between each row
        Returns:
        Vertical spacing

      • setVerticalSpacing

        public GridLayout setVerticalSpacing​(int verticalSpacing)
        Sets the vertical spacing, i.e. the number of empty columns between each row
        Parameters:
        verticalSpacing - New vertical spacing
        Returns:
        Itself

      • getTopMarginSize

        public int getTopMarginSize()
        Returns the top margin, i.e. number of empty rows above the first row in the grid
        Returns:
        Top margin, in number of rows

      • setTopMarginSize

        public GridLayout setTopMarginSize​(int topMarginSize)
        Sets the top margin, i.e. number of empty rows above the first row in the grid
        Parameters:
        topMarginSize - Top margin, in number of rows
        Returns:
        Itself

      • getBottomMarginSize

        public int getBottomMarginSize()
        Returns the bottom margin, i.e. number of empty rows below the last row in the grid
        Returns:
        Bottom margin, in number of rows

      • setBottomMarginSize

        public GridLayout setBottomMarginSize​(int bottomMarginSize)
        Sets the bottom margin, i.e. number of empty rows below the last row in the grid
        Parameters:
        bottomMarginSize - Bottom margin, in number of rows
        Returns:
        Itself

      • getLeftMarginSize

        public int getLeftMarginSize()
        Returns the left margin, i.e. number of empty columns left of the first column in the grid
        Returns:
        Left margin, in number of columns

      • setLeftMarginSize

        public GridLayout setLeftMarginSize​(int leftMarginSize)
        Sets the left margin, i.e. number of empty columns left of the first column in the grid
        Parameters:
        leftMarginSize - Left margin, in number of columns
        Returns:
        Itself

      • getRightMarginSize

        public int getRightMarginSize()
        Returns the right margin, i.e. number of empty columns right of the last column in the grid
        Returns:
        Right margin, in number of columns

      • setRightMarginSize

        public GridLayout setRightMarginSize​(int rightMarginSize)
        Sets the right margin, i.e. number of empty columns right of the last column in the grid
        Parameters:
        rightMarginSize - Right margin, in number of columns
        Returns:
        Itself

      • hasChanged

        public boolean hasChanged()
        Description copied from interface: LayoutManager
        Returns true if the internal state of this LayoutManager has changed since the last call to doLayout. This will tell the container that it needs to call doLayout again.
        Specified by:
        hasChanged in interface LayoutManager
        Returns:
        true if this layout manager's internal state has changed since the last call to doLayout

      • getPreferredSize

        public TerminalSize getPreferredSize​(java.util.List<Component> components)
        Description copied from interface: LayoutManager
        This method returns the dimensions it would prefer to have to be able to layout all components while giving all of them as much space as they are asking for.
        Specified by:
        getPreferredSize in interface LayoutManager
        Parameters:
        components - List of components
        Returns:
        Size the layout manager would like to have

      • doLayout

        public void doLayout​(TerminalSize area,
                     java.util.List<Component> components)
        Description copied from interface: LayoutManager
        Given a size constraint, update the location and size of each component in the component list by laying them out in the available area. This method will call setPosition(..) and setSize(..) on the Components.
        Specified by:
        doLayout in interface LayoutManager
        Parameters:
        area - Size available to this layout manager to lay out the components on
        components - List of components to lay out

      • getPreferredColumnWidths

        private int[] getPreferredColumnWidths​(Component[][] table)

      • getPreferredRowHeights

        private int[] getPreferredRowHeights​(Component[][] table)

      • getExpandableColumns

        private java.util.Set<java.lang.Integer> getExpandableColumns​(Component[][] table)

      • getExpandableRows

        private java.util.Set<java.lang.Integer> getExpandableRows​(Component[][] table)

      • shrinkWidthToFitArea

        private int shrinkWidthToFitArea​(TerminalSize area,
                                 int[] columnWidths)

      • shrinkHeightToFitArea

        private int shrinkHeightToFitArea​(TerminalSize area,
                                  int[] rowHeights)

      • grabExtraHorizontalSpace

        private int grabExtraHorizontalSpace​(TerminalSize area,
                                     int[] columnWidths,
                                     java.util.Set<java.lang.Integer> expandableColumns,
                                     int totalWidth)

      • grabExtraVerticalSpace

        private int grabExtraVerticalSpace​(TerminalSize area,
                                   int[] rowHeights,
                                   java.util.Set<java.lang.Integer> expandableRows,
                                   int totalHeight)

      • eliminateUnusedRowsAndColumns

        private Component[][] eliminateUnusedRowsAndColumns​(Component[][] table)