Package org.eclipse.swt.layout

Class FillLayout

java.lang.Object
org.eclipse.swt.widgets.Layout
org.eclipse.swt.layout.FillLayout
public final class FillLayout extends Layout
FillLayout is the simplest layout class. It lays out controls in a single row or column, forcing them to be the same size.

Initially, the controls will all be as tall as the tallest control, and as wide as the widest. FillLayout does not wrap, but you can specify margins and spacing. You might use it to lay out buttons in a task bar or tool bar, or to stack checkboxes in a Group. FillLayout can also be used when a Composite only has one child. For example, if a Shell has a single Group child, FillLayout will cause the Group to completely fill the Shell (if margins are 0).

Example code: first a FillLayout is created and its type field is set, and then the layout is set into the Composite. Note that in a FillLayout, children are always the same size, and they fill all available space. 

                FillLayout fillLayout = new FillLayout();
                fillLayout.type = SWT.VERTICAL;
                shell.setLayout(fillLayout);
See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    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 cell and the edge of its neighbouring cell.
    int
    type
    type specifies how controls will be positioned within the layout.

  • Constructor Summary

    Constructors
    Constructor
    Description
    FillLayout()
    Constructs a new instance of this class.
    FillLayout(int type)
    Constructs a new instance of this class given the type.

  • Method Summary

    Modifier and Type
    Method
    Description
    protected Point
    computeSize(Composite composite, int wHint, int hHint, boolean flushCache)
    Computes and returns the size of the specified composite's client area according to this layout.
    protected boolean
    flushCache(Control control)
    Instruct the layout to flush any cached values associated with the control specified in the argument control.
    protected void
    layout(Composite composite, boolean flushCache)
    Lays out the children of the specified composite according to this layout.
    String
    toString()
    Returns a string containing a concise, human-readable description of the receiver.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

  • Field Details

    • type

      public int type
      type specifies how controls will be positioned within the layout. The default value is HORIZONTAL. Possible values are:
      • HORIZONTAL: Position the controls horizontally from left to right
      • 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.
      Since:
      3.0

    • 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.
      Since:
      3.0

    • spacing

      public int spacing
      spacing specifies the number of points between the edge of one cell and the edge of its neighbouring cell. The default value is 0.
      Since:
      3.0

  • Constructor Details

    • FillLayout

      public FillLayout()
      Constructs a new instance of this class.

    • FillLayout

      public FillLayout(int type)
      Constructs a new instance of this class given the type.
      Parameters:
      type - the type of fill layout
      Since:
      2.0

  • Method Details

    • 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:

    • flushCache

      protected boolean flushCache(Control control)
      Description copied from class: Layout
      Instruct the layout to flush any cached values associated with the control specified in the argument control.
      Overrides:
      flushCache in class Layout
      Parameters:
      control - a control managed by this layout
      Returns:
      true if the Layout has flushed all cached information associated with control

    • 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

    • toString

      public String toString()
      Returns a string containing a concise, human-readable description of the receiver.
      Overrides:
      toString in class Object
      Returns:
      a string representation of the layout