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POJApplet/JPanel not receiving KeyListener events!
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copied!<p>I cannot get my JPanel within my JApplet to receive keyboard events. I CANNOT FATHOM why!</p> <p><strong>Note that...</strong></p> <ol> <li><p>Clicking the panel (with mouse) before typing makes no difference. This is by far the most common advice I see given on the Net.</p></li> <li><p>I have tried using the 'low-level' java.awt.KeyEventDispatcher interface. That makes no different either!</p></li> <li><p>However, if I use Applet instead of JApplet, then the Applet DOES receive keyboard events. But even here, the moment I add a Panel to this Applet (the Panel is really where all my app/painting logic is), I once again stop receiving kb events (in my Panel)!</p></li> <li><p>Now, I cannot simply use Applet (instead of JApplet) because, among other things, its onPaint gets a Graphics (instead of a Graphics2D object). So, #3 is NOT a solution for me.</p></li> <li><p>Things work like a charm in AppletViewer that comes with JDK.</p></li> </ol> <p>I desperately need someone's help here. Spent last 2-3 days trying all kinds of permutations I don't even recall now.</p> <p><strong>My platform details:</strong></p> <ol> <li><p>Firefox 3.5.3</p></li> <li><p>Fedora 11 on x86 (with latest updates/patches)</p></li> <li><p>Java Plugin: tried both of these, made no difference.</p> <p>3.1 IcedTea Java Web Browser Plugin 1.6 (fedora-29.b16.fc11-i386)</p> <p>3.2 jdk1.6.0_16/jre/plugin/i386/ns7/libjavaplugin_oji.so</p></li> <li><p>Used the above jdk1.6.0_16 to compile my applet source.</p></li> </ol> <p>Here's my code. Will greatly appreciate to hear from my fellow programmers... as I'm completely stuck!</p> <p>Thanks,</p> <p>/SD</p> <pre><code>import java.awt.event.*; import java.awt.*; import javax.swing.*; import javax.swing.event.*; class MyAppletKeyListener implements KeyListener, MouseListener { public void keyPressed(KeyEvent e) { System.out.println("panel:keyPressed" + e.getKeyChar()); } public void keyReleased(KeyEvent e) { } public void keyTyped(KeyEvent e) { System.out.println("panel:keyTyped" + e.getKeyChar()); } public void mouseClicked(MouseEvent e) { System.out.println("panel:mouseClicked"); } public void mouseEntered(MouseEvent e) { } public void mouseExited(MouseEvent e) { } public void mousePressed(MouseEvent e) { } public void mouseReleased(MouseEvent e) { } } public class TestApplet extends JApplet implements MouseListener { public void init() { System.out.println("applet:init"); MyAppletKeyListener listener = new MyAppletKeyListener(); // Panel related // Note: I'd like this red panel to handle // all my keyboard and mouse events. JPanel panel = new JPanel(); panel.setLayout(new FlowLayout()); panel.add(new JButton("test")); panel.add(new JButton("test2")); panel.setFocusable(true); panel.requestFocus(); panel.setBackground(new Color(200, 0, 0)); panel.addKeyListener(listener); panel.addMouseListener(listener); // applet related // Note: Added this only for debugging. I do NOT want // to handle my mouse/kb events in the applet. addMouseListener(this); getContentPane().setLayout(new FlowLayout()); getContentPane().add(panel); } public void mouseClicked(MouseEvent e) { System.out.println("applet:mouseClicked"); } public void mouseEntered(MouseEvent e) { } public void mouseExited(MouseEvent e) { } public void mousePressed(MouseEvent e) { } public void mouseReleased(MouseEvent e) { } } </code></pre> <p>The HTML:</p> <pre><code><html> <head> </head> <body> <applet id="myApplet" code="TestApplet.class" width="425" height="150" > </applet> </body> </html> </code></pre>

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