Class 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 TypeFieldDescriptionint
marginHeight specifies the number of points of vertical margin that will be placed along the top and bottom edges of the layout.int
marginWidth specifies the number of points of horizontal margin that will be placed along the left and right edges of the layout.topControl the Control that is displayed at the top of the stack. -
Constructor Summary
-
Method Summary
Modifier and TypeMethodDescriptionprotected 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 argumentcontrol
.protected void
Lays out the children of the specified composite according to this layout.toString()
Returns a string containing a concise, human-readable description of the receiver.
-
Field Details
-
marginWidth
public int marginWidthmarginWidth 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 marginHeightmarginHeight 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. -
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 Details
-
StackLayout
public StackLayout()
-
-
Method Details
-
computeSize
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 classLayout
- Parameters:
composite
- a composite widget using this layoutwHint
- 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"
-
flushCache
Description copied from class:Layout
Instruct the layout to flush any cached values associated with the control specified in the argumentcontrol
.- Overrides:
flushCache
in classLayout
- Parameters:
control
- a control managed by this layout- Returns:
- true if the Layout has flushed all cached information associated with control
-
layout
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.
-
toString
Returns a string containing a concise, human-readable description of the receiver.
-