| /******************************************************************************* |
| * Copyright (c) 2000, 2016 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 |
| *******************************************************************************/ |
| package org.eclipse.swt.snippets; |
| |
| import org.eclipse.swt.*; |
| import org.eclipse.swt.graphics.*; |
| import org.eclipse.swt.layout.*; |
| import org.eclipse.swt.widgets.*; |
| |
| /* |
| * Region on a control: create a non-rectangular button |
| * |
| * For a list of all SWT example snippets see |
| * http://www.eclipse.org/swt/snippets/ |
| * |
| * @since 3.4 |
| */ |
| |
| public class Snippet294 { |
| |
| static int[] circle(int r, int offsetX, int offsetY) { |
| int[] polygon = new int[8 * r + 4]; |
| // x^2 + y^2 = r^2 |
| for (int i = 0; i < 2 * r + 1; i++) { |
| int x = i - r; |
| int y = (int)Math.sqrt(r*r - x*x); |
| polygon[2*i] = offsetX + x; |
| polygon[2*i+1] = offsetY + y; |
| polygon[8*r - 2*i - 2] = offsetX + x; |
| polygon[8*r - 2*i - 1] = offsetY - y; |
| } |
| return polygon; |
| } |
| |
| public static void main(String[] args) { |
| final Display display = new Display(); |
| |
| final Shell shell = new Shell(display); |
| shell.setText("Regions on a Control"); |
| shell.setLayout(new FillLayout()); |
| shell.setBackground(display.getSystemColor(SWT.COLOR_DARK_RED)); |
| |
| Button b2 = new Button(shell, SWT.PUSH); |
| b2.setText("Button with Regions"); |
| |
| // define a region that looks like a circle with two holes in ot |
| Region region = new Region(); |
| region.add(circle(67, 87, 77)); |
| region.subtract(circle(20, 87, 47)); |
| region.subtract(circle(20, 87, 113)); |
| |
| // define the shape of the button using setRegion |
| b2.setRegion(region); |
| b2.setLocation(100,50); |
| |
| b2.addListener(SWT.Selection, e -> shell.close()); |
| |
| shell.setSize(200,200); |
| shell.open(); |
| |
| while (!shell.isDisposed()) { |
| if (!display.readAndDispatch()) |
| display.sleep(); |
| } |
| region.dispose(); |
| display.dispose(); |
| } |
| |
| } |