Class BorderLayout


  • public class BorderLayout
    extends Layout
    BorderLayout places controls in five regions
     +--------------------------------+
     |       NORTH / TOP              |
     +---+------------------------+---+
     |   |                        |   |
     | W |                        | E |
     | E |                        | A |
     | S |                        | S |
     | T |                        | T |
     | / |                        | / |
     | L |       CENTER           | R |
     | E |                        | I |
     | F |                        | G |
     | T |                        | H |
     |   |                        | T |
     |   |                        |   |
     +---+------------------------+---+
     |       SOUTH / BOTTOM           |
     +--------------------------------+
     
    The controls at the NORTH/SOUTH borders get their preferred heights, the controls at the EAST/WEST get their preferred widths and the center region grow/shrink according to the remaining space. If more than one control is placed inside a region the controls are equally distributed across their axis where the grow (CENTER controlled by the type value)
    Since:
    3.119
    • Field Summary

      Fields 
      Modifier and Type Field Description
      int controlSpacing
      controlSpacing specifies the number of points between the edge of one control and its neighboring control inside a region.
      double heightDistributionFactor
      If the height of the SWT.TOP and SWT.BOTTOM region exceeds the available space this factor is used to distribute the size to the controls, valid values range between [0 ... 1] The default value is 0.5 (equal distribution of available space)
      int marginHeight
      marginHeight specifies the number of points of vertical margin that will be placed along the top and bottom edges of the layout.
      int marginWidth
      marginWidth specifies the number of points of horizontal margin that will be placed along the left and right edges of the layout.
      int spacing
      spacing specifies the number of points between the edge of one region and its neighboring regions.
      int type
      type specifies how controls will be positioned within the center region.
      double widthDistributionFactor
      If the width of the SWT.LEFT and SWT.RIGHT region exceeds the available space this factor is used to distribute the size to the controls, valid values range between [0 ... 1] The default value is 0.5 (equal distribution of available space)
    • Constructor Summary

      Constructors 
      Constructor Description
      BorderLayout()  
    • Field Detail

      • type

        public int type
        type specifies how controls will be positioned within the center region. The default value is SWT.HORIZONTAL. Possible values are:
        • SWT.HORIZONTAL: Position the controls horizontally from left to right
        • SWT.VERTICAL: Position the controls vertically from top to bottom
      • marginWidth

        public int marginWidth
        marginWidth specifies the number of points of horizontal margin that will be placed along the left and right edges of the layout. The default value is 0.
      • marginHeight

        public int marginHeight
        marginHeight specifies the number of points of vertical margin that will be placed along the top and bottom edges of the layout. The default value is 0.
      • spacing

        public int spacing
        spacing specifies the number of points between the edge of one region and its neighboring regions. The default value is 0.
      • controlSpacing

        public int controlSpacing
        controlSpacing specifies the number of points between the edge of one control and its neighboring control inside a region. The default value is 0.
      • widthDistributionFactor

        public double widthDistributionFactor
        If the width of the SWT.LEFT and SWT.RIGHT region exceeds the available space this factor is used to distribute the size to the controls, valid values range between [0 ... 1] The default value is 0.5 (equal distribution of available space)
      • heightDistributionFactor

        public double heightDistributionFactor
        If the height of the SWT.TOP and SWT.BOTTOM region exceeds the available space this factor is used to distribute the size to the controls, valid values range between [0 ... 1] The default value is 0.5 (equal distribution of available space)
    • Constructor Detail

      • BorderLayout

        public BorderLayout()
    • Method Detail

      • computeSize

        protected Point computeSize​(Composite composite,
                                    int wHint,
                                    int hHint,
                                    boolean flushCache)
        Description copied from class: Layout
        Computes and returns the size of the specified composite's client area according to this layout.

        This method computes the size that the client area of the composite must be in order to position all children at their preferred size inside the composite according to the layout algorithm encoded by this layout.

        When a width or height hint is supplied, it is used to constrain the result. For example, if a width hint is provided that is less than the width of the client area, the layout may choose to wrap and increase height, clip, overlap, or otherwise constrain the children.

        Specified by:
        computeSize in class Layout
        Parameters:
        composite - a composite widget using this layout
        wHint - width (SWT.DEFAULT for preferred size)
        hHint - height (SWT.DEFAULT for preferred size)
        flushCache - true means flush cached layout values
        Returns:
        a point containing the computed size (width, height)
        See Also:
        Layout.layout(org.eclipse.swt.widgets.Composite, boolean), Control.getBorderWidth(), Control.getBounds(), Control.getSize(), Control.pack(boolean), "computeTrim, getClientArea for controls that implement them"
      • layout

        protected void layout​(Composite composite,
                              boolean flushCache)
        Description copied from class: Layout
        Lays out the children of the specified composite according to this layout.

        This method positions and sizes the children of a composite using the layout algorithm encoded by this layout. Children of the composite are positioned in the client area of the composite. The position of the composite is not altered by this method.

        When the flush cache hint is true, the layout is instructed to flush any cached values associated with the children. Typically, a layout will cache the preferred sizes of the children to avoid the expense of computing these values each time the widget is laid out.

        When layout is triggered explicitly by the programmer the flush cache hint is true. When layout is triggered by a resize, either caused by the programmer or by the user, the hint is false.

        Specified by:
        layout in class Layout
        Parameters:
        composite - a composite widget using this layout
        flushCache - true means flush cached layout values