import javax.swing.*; import java.awt.*; import java.awt.event.*; import java.net.*; /** * @author jag * @author mem * @author kwalrath */ public class TumbleItem extends JApplet implements ActionListener { int loopslot = -1; //the current frame number String dir; //the directory relative to the codebase //from which the images are loaded Timer timer; //the timer animating the images int pause; //the length of the pause between revs int offset; //how much to offset between loops int off; //the current offset int speed; //animation speed int nimgs; //number of images to animate int width; //width of the applet's content pane JComponent contentPane; //the applet's content pane ImageIcon imgs[]; //the images int maxWidth; //width of widest image boolean finishedLoading = false; JLabel statusLabel; static Color[] labelColor = { Color.black, Color.black, Color.black, Color.black, Color.black, Color.white, Color.white, Color.white, Color.white, Color.white }; public void init() { //Get the applet parameters. String at = getParameter("img"); dir = (at != null) ? at : "images/tumble"; at = getParameter("pause"); pause = (at != null) ? Integer.valueOf(at).intValue() : 1900; at = getParameter("offset"); offset = (at != null) ? Integer.valueOf(at).intValue() : 0; at = getParameter("speed"); speed = (at != null) ? (1000 / Integer.valueOf(at).intValue()) : 100; at = getParameter("nimgs"); nimgs = (at != null) ? Integer.valueOf(at).intValue() : 16; at = getParameter("maxwidth"); maxWidth = (at != null) ? Integer.valueOf(at).intValue() : 0; //Animate from right to left if offset is negative. width = getSize().width; if (offset < 0) { off = width - maxWidth; } //Custom component to draw the current image //at a particular offset. contentPane = new JPanel() { public void paintComponent(Graphics g) { super.paintComponent(g); if (finishedLoading && (loopslot > -1) && (loopslot < nimgs)) { imgs[loopslot].paintIcon(this, g, off, 0); } } }; contentPane.setBackground(Color.white); setContentPane(contentPane); //Put a "Loading Images..." label in the middle of //the content pane. To center the label's text in //the applet, put it in the center part of a //BorderLayout-controlled container, and center-align //the label's text. statusLabel = new JLabel("Loading Images...", JLabel.CENTER); statusLabel.setForeground(labelColor[0]); contentPane.setLayout(new BorderLayout()); contentPane.add(statusLabel, BorderLayout.CENTER); //Set up the timer that will perform the animation. //Don't start it until all the images are loaded. timer = new Timer(speed, this); timer.setInitialDelay(pause); timer.setCoalesce(false); //Loading the images can take quite a while, so to //avoid staying in init() (and thus not being able //to show the "Loading Images..." label, we'll //load the images in a SwingWorker thread. imgs = new ImageIcon[nimgs]; timer.start(); //Start the animation. final SwingWorker worker = new SwingWorker() { public Object construct() { URL baseURL = getCodeBase(); String prefix = dir + "/T"; //Images are numbered 1 to nimgs, //but fill array from 0 to nimgs-1. for (int i = 0; i < nimgs; i++) { imgs[i] = new ImageIcon(getURL(baseURL, prefix + (i+1) + ".gif")); } finishedLoading = true; return imgs; } public void finished() { //Remove the "Loading images" label. contentPane.removeAll(); contentPane.repaint(); loopslot = -1; } }; worker.start(); } //Update the the loopslot (frame number) and the offset. //If it's the last frame, restart the timer to get a long //pause between loops. public void actionPerformed(ActionEvent e) { loopslot++; if (!finishedLoading) { int colorIndex = loopslot % labelColor.length; try { statusLabel.setForeground(labelColor[colorIndex]); } catch (NullPointerException exc) {} return; } if (loopslot >= nimgs) { loopslot = 0; off += offset; if (off < 0) { off = width - maxWidth; } else if (off + maxWidth > width) { off = 0; } } contentPane.repaint(); if (loopslot == nimgs - 1) { timer.restart(); } } public void start() { if (finishedLoading && (nimgs > 1)) { timer.restart(); } } public void stop() { timer.stop(); } protected URL getURL(URL codeBase, String filename) { URL url = null; try { url = new URL(codeBase, filename); } catch (java.net.MalformedURLException e) { System.out.println("Couldn't create image: badly specified URL"); return null; } return url; } public String getAppletInfo() { return "Title: TumbleItem v1.2, 23 Jul 1997\n" + "Author: James Gosling\n" + "A simple Item class to play an image loop."; } public String[][] getParameterInfo() { String[][] info = { {"img", "string", "the directory containing the images to loop"}, {"pause", "int", "pause between complete loops; default is 3900"}, {"offset", "int", "offset of each image to simulate left (-) or " + "right (+) motion; default is 0 (no motion)"}, {"speed", "int", "the speed at which the frames are looped; " + "default is 100"}, {"nimgs", "int", "the number of images to be looped; default is 16"}, {"maxwidth", "int", "the maximum width of any image in the loop; " + "default is 0"} }; return info; } }