| /******************************************************************************* |
| * Copyright (c) 2000, 2018 IBM Corporation and others. |
| * |
| * This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License 2.0 |
| * which accompanies this distribution, and is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * |
| * SPDX-License-Identifier: EPL-2.0 |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| package org.eclipse.swt.custom; |
| |
| |
| import org.eclipse.swt.*; |
| import org.eclipse.swt.graphics.*; |
| import org.eclipse.swt.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, 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(); |
| * } |
| * } |
| * </code></pre> |
| * |
| * @see <a href="http://www.eclipse.org/swt/snippets/#stacklayout">StackLayout snippets</a> |
| * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: LayoutExample</a> |
| * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a> |
| */ |
| |
| public class StackLayout extends Layout { |
| |
| /** |
| * 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. |
| */ |
| public int marginWidth = 0; |
| /** |
| * 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. |
| */ |
| 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; |
| |
| @Override |
| protected Point computeSize(Composite composite, int wHint, int hHint, boolean 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 != SWT.DEFAULT) width = wHint; |
| if (hHint != SWT.DEFAULT) height = hHint; |
| return new Point(width, height); |
| } |
| |
| @Override |
| protected boolean flushCache(Control control) { |
| return true; |
| } |
| |
| @Override |
| protected void layout(Composite composite, boolean 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] == topControl); |
| } |
| } |
| |
| String getName () { |
| String string = getClass ().getName (); |
| int index = string.lastIndexOf ('.'); |
| if (index == -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 |
| */ |
| @Override |
| public String toString () { |
| String string = getName ()+" {"; |
| if (marginWidth != 0) string += "marginWidth="+marginWidth+" "; |
| if (marginHeight != 0) string += "marginHeight="+marginHeight+" "; |
| if (topControl != null) string += "topControl="+topControl+" "; |
| string = string.trim(); |
| string += "}"; |
| return string; |
| } |
| } |