Java tutorial
/******************************************************************************* * Copyright (c) 2008, 2016 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.snippets; /* * Create a ToolBar containing animated GIFs * * For a list of all SWT example snippets see * http://www.eclipse.org/swt/snippets/ */ import java.io.*; import org.eclipse.swt.*; import org.eclipse.swt.graphics.*; import org.eclipse.swt.widgets.*; public class Snippet288 { static Display display; static Shell shell; static GC shellGC; static Color shellBackground; static ImageLoader[] loader; static ImageData[][] imageDataArray; static Thread animateThread[]; static Image[][] image; private static ToolItem item[]; static final boolean useGIFBackground = false; public static void main(String[] args) { display = new Display(); Shell shell = new Shell(display); shell.setText("Snippet 288"); shellBackground = shell.getBackground(); FileDialog dialog = new FileDialog(shell, SWT.OPEN | SWT.MULTI); dialog.setText("Select Multiple Animated GIFs"); dialog.setFilterExtensions(new String[] { "*.gif" }); String filename = dialog.open(); String filenames[] = dialog.getFileNames(); int numToolBarItems = filenames.length; if (numToolBarItems > 0) { try { loadAllImages(new File(filename).getParent(), filenames); } catch (SWTException e) { System.err.println("There was an error loading an image."); e.printStackTrace(); } ToolBar toolBar = new ToolBar(shell, SWT.FLAT | SWT.BORDER | SWT.WRAP); item = new ToolItem[numToolBarItems]; for (int i = 0; i < numToolBarItems; i++) { item[i] = new ToolItem(toolBar, SWT.PUSH); item[i].setImage(image[i][0]); } toolBar.pack(); shell.open(); startAnimationThreads(); while (!shell.isDisposed()) { if (!display.readAndDispatch()) display.sleep(); } for (int i = 0; i < numToolBarItems; i++) { for (int j = 0; j < image[i].length; j++) { image[i][j].dispose(); } } } display.dispose(); } private static void loadAllImages(String directory, String[] filenames) throws SWTException { int numItems = filenames.length; loader = new ImageLoader[numItems]; imageDataArray = new ImageData[numItems][]; image = new Image[numItems][]; for (int i = 0; i < numItems; i++) { loader[i] = new ImageLoader(); int fullWidth = loader[i].logicalScreenWidth; int fullHeight = loader[i].logicalScreenHeight; imageDataArray[i] = loader[i].load(directory + File.separator + filenames[i]); int numFramesOfAnimation = imageDataArray[i].length; image[i] = new Image[numFramesOfAnimation]; for (int j = 0; j < numFramesOfAnimation; j++) { if (j == 0) { //for the first frame of animation, just draw the first frame image[i][j] = new Image(display, imageDataArray[i][j]); fullWidth = imageDataArray[i][j].width; fullHeight = imageDataArray[i][j].height; } else { //after the first frame of animation, draw the background or previous frame first, then the new image data image[i][j] = new Image(display, fullWidth, fullHeight); GC gc = new GC(image[i][j]); gc.setBackground(shellBackground); gc.fillRectangle(0, 0, fullWidth, fullHeight); ImageData imageData = imageDataArray[i][j]; switch (imageData.disposalMethod) { case SWT.DM_FILL_BACKGROUND: /* Fill with the background color before drawing. */ Color bgColor = null; if (useGIFBackground && loader[i].backgroundPixel != -1) { bgColor = new Color(display, imageData.palette.getRGB(loader[i].backgroundPixel)); } gc.setBackground(bgColor != null ? bgColor : shellBackground); gc.fillRectangle(imageData.x, imageData.y, imageData.width, imageData.height); if (bgColor != null) bgColor.dispose(); break; default: /* Restore the previous image before drawing. */ gc.drawImage(image[i][j - 1], 0, 0, fullWidth, fullHeight, 0, 0, fullWidth, fullHeight); break; } Image newFrame = new Image(display, imageData); gc.drawImage(newFrame, 0, 0, imageData.width, imageData.height, imageData.x, imageData.y, imageData.width, imageData.height); newFrame.dispose(); gc.dispose(); } } } } private static void startAnimationThreads() { animateThread = new Thread[image.length]; for (int ii = 0; ii < image.length; ii++) { final int i = ii; animateThread[i] = new Thread("Animation " + i) { int imageDataIndex = 0; @Override public void run() { try { int repeatCount = loader[i].repeatCount; while (loader[i].repeatCount == 0 || repeatCount > 0) { imageDataIndex = (imageDataIndex + 1) % imageDataArray[i].length; if (!display.isDisposed()) { display.asyncExec(() -> { if (!item[i].isDisposed()) item[i].setImage(image[i][imageDataIndex]); }); } else { break; } /* Sleep for the specified delay time (adding commonly-used slow-down fudge factors). */ try { int ms = imageDataArray[i][imageDataIndex].delayTime * 10; if (ms < 20) ms += 30; if (ms < 30) ms += 10; Thread.sleep(ms); } catch (InterruptedException e) { } /* If we have just drawn the last image, decrement the repeat count and start again. */ if (imageDataIndex == imageDataArray[i].length - 1) repeatCount--; } } catch (SWTException ex) { System.out.println("There was an error animating the GIF"); ex.printStackTrace(); } } }; animateThread[i].setDaemon(true); animateThread[i].start(); } } }