Create non-rectangular shell from an image with transparency : Shell « SWT « Java Tutorial






Create non-rectangular shell from an image with transparency
/*******************************************************************************
 * Copyright (c) 2000, 2005 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.SWT;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.graphics.Region;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Shell;

/**
 * Region snippet: Create non-rectangular shell from an image with transparency
 * 
 * For a list of all SWT example snippets see
 * http://www.eclipse.org/swt/snippets/
 * 
 * @since 3.2
 */
public class NonRectangularShellFromTransparencyImage {
  public static void main(String[] args) {
    final Display display = new Display();
    final Image image = display.getSystemImage(SWT.ICON_INFORMATION);
    final Shell shell = new Shell(display, SWT.NO_TRIM);
    Region region = new Region();
    final ImageData imageData = image.getImageData();
    if (imageData.alphaData != null) {
      Rectangle pixel = new Rectangle(0, 0, 1, 1);
      for (int y = 0; y < imageData.height; y++) {
        for (int x = 0; x < imageData.width; x++) {
          if (imageData.getAlpha(x, y) == 255) {
            pixel.x = imageData.x + x;
            pixel.y = imageData.y + y;
            region.add(pixel);
          }
        }
      }
    } else {
      ImageData mask = imageData.getTransparencyMask();
      Rectangle pixel = new Rectangle(0, 0, 1, 1);
      for (int y = 0; y < mask.height; y++) {
        for (int x = 0; x < mask.width; x++) {
          if (mask.getPixel(x, y) != 0) {
            pixel.x = imageData.x + x;
            pixel.y = imageData.y + y;
            region.add(pixel);
          }
        }
      }
    }
    shell.setRegion(region);

    Listener l = new Listener() {
      int startX, startY;

      public void handleEvent(Event e) {
        if (e.type == SWT.KeyDown && e.character == SWT.ESC) {
          shell.dispose();
        }
        if (e.type == SWT.MouseDown && e.button == 1) {
          startX = e.x;
          startY = e.y;
        }
        if (e.type == SWT.MouseMove && (e.stateMask & SWT.BUTTON1) != 0) {
          Point p = shell.toDisplay(e.x, e.y);
          p.x -= startX;
          p.y -= startY;
          shell.setLocation(p);
        }
        if (e.type == SWT.Paint) {
          e.gc.drawImage(image, imageData.x, imageData.y);
        }
      }
    };
    shell.addListener(SWT.KeyDown, l);
    shell.addListener(SWT.MouseDown, l);
    shell.addListener(SWT.MouseMove, l);
    shell.addListener(SWT.Paint, l);

    shell.setSize(imageData.x + imageData.width, imageData.y + imageData.height);
    shell.open();
    while (!shell.isDisposed()) {
      if (!display.readAndDispatch())
        display.sleep();
    }
    region.dispose();
    image.dispose();
    display.dispose();
  }
}








17.4.Shell
17.4.1.Understanding the Shell Object
17.4.2.Creating Shells
17.4.3.Open a shell minimized (iconified)
17.4.4.Open a shell maximized (full screen)
17.4.5.Center a shell on the primary monitorCenter a shell on the primary monitor
17.4.6.Set icons with different resolutions
17.4.7.Create a non-rectangular windowCreate a non-rectangular window
17.4.8.Create a non-rectangular shell to simulate transparencyCreate a non-rectangular shell to simulate transparency
17.4.9.Create non-rectangular shell from an image with transparencyCreate non-rectangular shell from an image with transparency
17.4.10.Allow escape to close a shellAllow escape to close a shell
17.4.11.Prevent a shell from closing (prompt the user)Prevent a shell from closing (prompt the user)
17.4.12.Create GC from Shell and paint on windowCreate GC from Shell and paint on window
17.4.13.Getting Controls on a shellGetting Controls on a shell
17.4.14.Set default Button for ShellSet default Button for Shell
17.4.15.Get Default ButtonGet Default Button
17.4.16.Shell with SWT.SHELL_TRIM|SWT.TOOL styleShell with SWT.SHELL_TRIM|SWT.TOOL style
17.4.17.Ring ShellRing Shell
17.4.18.Set left upper corner imageSet left upper corner image
17.4.19.Shell without Title bar
17.4.20.ON_TOP: This style bit causes the shell to always float on the top of the desktop.
17.4.21.SHELL_TRIM = (CLOSE | TITLE | MIN | MAX | RESIZE): top-level shells.SHELL_TRIM = (CLOSE | TITLE | MIN | MAX | RESIZE): top-level shells.
17.4.22.DIALOG_TRIM = (CLOSE | TITLE | BORDER): dialog shells.
17.4.23.The modal state of shells: APPLICATION_MODAL, MODELESS, PRIMARY_MODAL, SYSTEM_MODAL
17.4.24.TOOL: the shell is a tool window(floating toolbars)
17.4.25.Shell States
17.4.26.Setting the Title