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copied!<blockquote> <p>How would I fix this bug?</p> </blockquote> <p>Not really a bug as much as incompatiblity.</p> <blockquote> <p>If there is an alternative to KeyListener that will do the same thing, please let me know and preferably provide an example of how it would work.</p> </blockquote> <p>Dont use <code>KeyListener</code>/<code>KeyAdapter</code> for Swing components as there is focus issues, which can be gotten around by calling <code>requestFocusInWindow()</code> on the component after its visible to make sure it has focus and of course <code>setFoucsable(true);</code> must be called if component is not <em>focusable</em> like a <code>JLabel</code>.</p> <p>Swing components should use <a href="http://docs.oracle.com/javase/tutorial/uiswing/misc/keybinding.html" rel="nofollow"><code>KeyBinding</code>s</a>, which overcomes the above mentioned problems by automatically calling <code>setFocusable(true)</code> on the component to which <code>KeyBinding</code> is added etc.</p> <p>Here is a small example:</p> <pre><code>void addKeyBinding(JComponent jc) { jc.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke(KeyEvent.VK_A, 0, false), "A pressed"); jc.getActionMap().put("esc pressed", new AbstractAction() { @Override public void actionPerformed(ActionEvent ae) { System.out.println("A pressed"); } }); jc.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke(KeyEvent.VK_A, 0, true), "A released"); jc.getActionMap().put("A released", new AbstractAction() { @Override public void actionPerformed(ActionEvent ae) { System.out.println("A released"); } }); } </code></pre> <p>you would call this method with the instance of the <code>JComponent</code> i.e <code>JPanel</code> etc that you want to add the <code>Keybinding</code> too:</p> <pre><code>JPanel p=new JPanel(); addKeyBinding(p); </code></pre> <p><strong>Other suggestions on code:</strong></p> <ul> <li><p>Always create Swing components on <code>Event Dispatch Thread</code> via <code>SwingUtilities.invokeXXX</code> block</p></li> <li><p>Dont implement an <code>Listener</code> like <code>ActionListener</code> on the class itself unless this class will be used as a <code>Listener</code> <strong>only</strong>, or you want to expose the implementing classes/<code>Listeners</code> methods to other classes.</p></li> </ul>

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