Standard Widget Toolkit for GTK 3.125.0 · org.eclipse.swt.custom.StackLayout

This Layout stacks all the controls one on top of the other and resizes all controls to have the same size and location. The control specified in topControl is visible and all other controls are not visible. Users must set the topControl value to flip between the visible items and then call layout() on the composite which has the StackLayout.

Here is an example which places ten buttons in a stack layout and flips between them:


	public static void main(String[] args) {
		Display display = new Display();
		Shell shell = new Shell(display);
		shell.setLayout(new GridLayout());

		final Composite parent = new Composite(shell, SWT.NONE);
		parent.setLayoutData(new GridData(GridData.FILL_BOTH));
		final StackLayout layout = new StackLayout();
		parent.setLayout(layout);
		final Button[] bArray = new Button[10];
		for (int i = 0; i < 10; i++) {
			bArray[i] = new Button(parent, SWT.PUSH);
			bArray[i].setText("Button "+i);
		}
		layout.topControl = bArray[0];

		Button b = new Button(shell, SWT.PUSH);
		b.setText("Show Next Button");
		final int[] index = new int[1];
		b.addListener(SWT.Selection, new Listener(){
			public void handleEvent(Event e) {
				index[0] = (index[0] + 1) % 10;
				layout.topControl = bArray[index[0]];
				parent.layout();
			}
		});

		shell.open();
		while (shell != null && !shell.isDisposed()) {
			if (!display.readAndDispatch())
				display.sleep();
		}
	}

Field Summary

Modifier and Type	Field and Description
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.
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.
public Control	topControl topControl the Control that is displayed at the top of the stack.

Constructor Summary

Access	Constructor and Description
public	StackLayout()

Method Summary

Modifier and Type	Method and Description
protected Point	computeSize(Composite a composite widget using this layout composite, int width (`SWT.DEFAULT` for preferred size) wHint, int height (`SWT.DEFAULT` for preferred size) hHint, boolean `true` means flush cached layout values flushCache) Implements abstract org.eclipse.swt.widgets.Layout.computeSize. Computes and returns the size of the specified composite's client area according to this layout.
protected boolean	flushCache(Control a control managed by this layout control) Overrides org.eclipse.swt.widgets.Layout.flushCache. Instruct the layout to flush any cached values associated with the control specified in the argument `control`.
pack-priv String	getName()
protected void	layout(Composite a composite widget using this layout composite, boolean `true` means flush cached layout values flushCache) Implements abstract org.eclipse.swt.widgets.Layout.layout. Lays out the children of the specified composite according to this layout.
public String	Returns: a string representation of the layout toString() Overrides java.lang.Object.toString. Returns a string containing a concise, human-readable description of the receiver.

Field Detail

marginHeight	back to summary
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.

marginWidth	back to summary
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.

topControl	back to summary
public Control topControl topControl the Control that is displayed at the top of the stack. All other controls that are children of the parent composite will not be visible.

Constructor Detail

StackLayout	back to summary
public StackLayout()

Method Detail

computeSize back to summary

computeSize	back to summary
protected Point computeSize(Composite composite, int wHint, int hHint, boolean flushCache) Implements abstract org.eclipse.swt.widgets.Layout.computeSize. Doc from org.eclipse.swt.widgets.Layout.computeSize. 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. Parameters composite:Composite a composite widget using this layout wHint:int width (`SWT.DEFAULT` for preferred size) hHint:int height (`SWT.DEFAULT` for preferred size) flushCache:boolean `true` means flush cached layout values Returns:Point a point containing the computed size (width, height) Annotations @Override

protected Point computeSize(Composite composite, int wHint, int hHint, boolean flushCache)

Implements abstract org.eclipse.swt.widgets.Layout.computeSize.

Doc from org.eclipse.swt.widgets.Layout.computeSize.

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.

Parameters

composite:Composite: a composite widget using this layout
wHint:int: width (SWT.DEFAULT for preferred size)
hHint:int: height (SWT.DEFAULT for preferred size)
flushCache:boolean: true means flush cached layout values

Returns:Point

a point containing the computed size (width, height)

Annotations

@Override

flushCache back to summary

flushCache	back to summary
protected boolean flushCache(Control control) Overrides org.eclipse.swt.widgets.Layout.flushCache. Doc from org.eclipse.swt.widgets.Layout.flushCache. Instruct the layout to flush any cached values associated with the control specified in the argument `control`. Parameters control:Control a control managed by this layout Returns:boolean true if the Layout has flushed all cached information associated with control Annotations @Override

protected boolean flushCache(Control control)

Overrides org.eclipse.swt.widgets.Layout.flushCache.

Doc from org.eclipse.swt.widgets.Layout.flushCache.

Instruct the layout to flush any cached values associated with the control specified in the argument control.

Parameters

control:Control: a control managed by this layout

Returns:boolean

true if the Layout has flushed all cached information associated with control

Annotations

@Override

getName	back to summary
pack-priv String getName()

layout back to summary

layout	back to summary
protected void layout(Composite composite, boolean flushCache) Implements abstract org.eclipse.swt.widgets.Layout.layout. Doc from org.eclipse.swt.widgets.Layout.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. Parameters composite:Composite a composite widget using this layout flushCache:boolean `true` means flush cached layout values Annotations @Override

protected void layout(Composite composite, boolean flushCache)

Implements abstract org.eclipse.swt.widgets.Layout.layout.

Doc from org.eclipse.swt.widgets.Layout.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.

Parameters

composite:Composite: a composite widget using this layout
flushCache:boolean: true means flush cached layout values

Annotations

@Override

toString	back to summary
public String toString() Overrides java.lang.Object.toString. Returns a string containing a concise, human-readable description of the receiver. Returns:String a string representation of the layout Annotations @Override

toString

back to summary

public String toString()

Overrides java.lang.Object.toString.

Returns a string containing a concise, human-readable description of the receiver.

Returns:String

a string representation of the layout

Annotations

@Override

public Class StackLayout

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail