/*******************************************************************************
* Copyright (c) 2000, 2014 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.widgets.*;
/**
* Region snippet: Create non-rectangular shell from an image with transparency
* (ESC to close shell)
*
* For a list of all SWT example snippets see
* http://www.eclipse.org/swt/snippets/
*
* @since 3.2
*/
public class Snippet219 {
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() {
/** The x/y of the MouseDown, relative to top-left of the shell. */
int startX, startY;
@Override
public void handleEvent(Event e) {
if (e.type == SWT.KeyDown && e.character == SWT.ESC) {
shell.dispose();
}
if (e.type == SWT.MouseDown && e.button == 1) {
Point p = shell.toDisplay(e.x, e.y);
Point loc = shell.getLocation();
startX = p.x - loc.x;
startY = p.y - loc.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.open ();
while (!shell.isDisposed ()) {
if (!display.readAndDispatch ()) display.sleep ();
}
region.dispose();
image.dispose ();
display.dispose ();
}
}
