tests/org.eclipse.swt.tests.gtk/ManualTests/org/eclipse/swt/tests/gtk/snippets/Bug547529_ImageLoaderStriping.java

/*******************************************************************************
 * Copyright (c) 2019 Patrick Tasse 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:
 *     Patrick Tasse - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.tests.gtk.snippets;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.graphics.ImageLoader;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.layout.RowLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.FileDialog;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Shell;

public class Bug547529_ImageLoaderStriping {

	public static void main(String[] args) {
		Display display = new Display();
		String gtkVersion = System.getProperty("org.eclipse.swt.internal.gtk.version");
		Shell shell = new Shell(display);
		shell.setText(gtkVersion);

		shell.setLayout(new FillLayout());

		Composite composite = new Composite(shell, SWT.NONE);
		composite.setLayout(new RowLayout(SWT.VERTICAL));
		Label label = new Label(composite, SWT.NONE);
		label.setText(gtkVersion);

		Button button = new Button(composite, SWT.PUSH);
		button.setText("Take Snapshot...");
		button.addSelectionListener(new SelectionAdapter() {
			@Override
			public void widgetSelected(SelectionEvent e) {
				FileDialog dialog = new FileDialog(shell, SWT.SAVE);
				dialog.setFilterExtensions(new String[] { "*.png" });
				dialog.setFilterIndex(0);
				dialog.setFileName("Untitled.png");
				String filename = dialog.open();
				if ((filename != null) && !filename.isEmpty()) {
					saveImage(composite, filename, SWT.IMAGE_PNG);
				}
			}
		});

		shell.pack();
		shell.open();
		while (!shell.isDisposed()) {
			if (!display.readAndDispatch()) {
				display.sleep();
			}
		}
		display.dispose();
	}

	private static void saveImage(Control control, String filename, int format) {
		Image image = new Image(control.getDisplay(), control.getBounds());
		GC gc = new GC(image);
		control.print(gc);
		gc.dispose();
		ImageData data = image.getImageData();
		ImageLoader loader = new ImageLoader();
		loader.data = new ImageData[] { data };
		loader.save(filename, format);
		image.dispose();
	}
}