|
 |
|
| |
org.eclipse.swt.custom
Class StackLayout
java.lang.Object
org.eclipse.swt.widgets.Layout
org.eclipse.swt.custom.StackLayout
- public class StackLayout
- extends
Layout
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
|
int
|
marginHeight
marginHeight specifies the number of pixels of vertical margin that will be
placed along the top and bottom edges of the layout. |
int
|
marginWidth
marginWidth specifies the number of pixels of horizontal margin that will
be placed along the left and right edges of the layout. |
Control
|
topControl
topControl the Control that is displayed at the top of the stack. |
|
Method Summary
|
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. |
marginWidth
public int marginWidth
- marginWidth specifies the number of pixels 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 pixels of vertical margin that will be
placed along the top and bottom edges of the layout. The default value is
0.
topControl
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.
StackLayout
public StackLayout()
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"
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.
-
-
Returns:
- a string representation of the layout
Copyright (c) Innoopract Informationssysteme GmbH and others 2002, 2008. All rights reserved.
|
|
|
