--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dwt/custom/StackLayout.d	Sat Aug 09 17:00:02 2008 +0200
@@ -0,0 +1,144 @@
+/*******************************************************************************
+ * Copyright (c) 2000, 2006 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     IBM Corporation - initial API and implementation
+ *******************************************************************************/
+module dwt.custom;
+
+
+import dwt.*;
+import dwt.graphics.*;
+import dwt.widgets.*;
+
+/**
+ * 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.
+ * 
+ * <p> Here is an example which places ten buttons in a stack layout and 
+ * flips between them:
+ * 
+ * <pre><code>
+ *  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, DWT.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 &lt; 10; i++) {
+ *          bArray[i] = new Button(parent, DWT.PUSH);
+ *          bArray[i].setText("Button "+i);
+ *      }
+ *      layout.topControl = bArray[0];
+ *  
+ *      Button b = new Button(shell, DWT.PUSH);
+ *      b.setText("Show Next Button");
+ *      final int[] index = new int[1];
+ *      b.addListener(DWT.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 !is null && !shell.isDisposed()) {
+ *          if (!display.readAndDispatch())
+ *              display.sleep(); 
+ *      }   
+ *  }
+ * </code></pre>
+ */
+
+public class StackLayout : Layout {
+    
+    /**
+     * 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.
+     */
+    public int marginWidth = 0;
+    /**
+     * 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.
+     */
+    public int marginHeight = 0;
+
+    /**
+     * 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.
+     */
+    public Control topControl;
+
+protected Point computeSize(Composite composite, int wHint, int hHint, bool flushCache) {
+    Control children[] = composite.getChildren();
+    int maxWidth = 0;
+    int maxHeight = 0;
+    for (int i = 0; i < children.length; i++) {
+        Point size = children[i].computeSize(wHint, hHint, flushCache);
+        maxWidth = Math.max(size.x, maxWidth);
+        maxHeight = Math.max(size.y, maxHeight);
+    }
+    int width = maxWidth + 2 * marginWidth;
+    int height = maxHeight + 2 * marginHeight;
+    if (wHint !is DWT.DEFAULT) width = wHint;
+    if (hHint !is DWT.DEFAULT) height = hHint;
+    return new Point(width, height);
+}
+
+protected bool flushCache(Control control) {
+    return true;
+}
+
+protected void layout(Composite composite, bool flushCache) {
+    Control children[] = composite.getChildren();
+    Rectangle rect = composite.getClientArea();
+    rect.x += marginWidth;
+    rect.y += marginHeight;
+    rect.width -= 2 * marginWidth;
+    rect.height -= 2 * marginHeight;
+    for (int i = 0; i < children.length; i++) {
+        children[i].setBounds(rect);
+        children[i].setVisible(children[i] is topControl);
+            
+    }
+}
+
+String getName () {
+    String String = getClass ().getName ();
+    int index = String.lastIndexOf ('.');
+    if (index is -1) return String;
+    return String.substring (index + 1, String.length ());
+}
+
+/**
+ * Returns a String containing a concise, human-readable
+ * description of the receiver.
+ *
+ * @return a String representation of the layout
+ */
+public String toString () {
+    String String = getName ()+" {";
+    if (marginWidth !is 0) String += "marginWidth="+marginWidth+" ";
+    if (marginHeight !is 0) String += "marginHeight="+marginHeight+" ";
+    if (topControl !is null) String += "topControl="+topControl+" ";
+    String = String.trim();
+    String += "}";
+    return String;
+}
+}