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POKeyListeners not responding when added to JFrame
 

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    <p>I've been reading the java documentation and am trying to understand key listeners and their uses. I managed to make a simple program where 'w' and 's' toggled the background colour, however when I tried to make them move a painted ball they stopped responding. I am fairly sure it isn't a painting issue as I read through the JavaDocs common painting issues. I've set the JFrame as focuseable (or at least I think I have). If anyone could point me In the right direction it would be greatly appreciated.</p> <p>Here is the main class</p> <pre><code>import javax.swing.JFrame; import java.awt.EventQueue; public class frame { public static void main(String[] args){ EventQueue.invokeLater(new Runnable() { @Override public void run() { showGui(); } }); } public static void showGui(){ JFrame f = new JFrame("Testing.."); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.setFocusable(true); f.add(new Gui()); f.setSize(300,300); f.setVisible(true); } } </code></pre> <p>and the Gui/KeyListener class</p> <pre><code>import java.awt.Color; import java.awt.Graphics; import java.awt.event.KeyEvent; import java.awt.event.KeyListener; import javax.swing.BorderFactory; import javax.swing.JPanel; @SuppressWarnings("serial") public class Gui extends JPanel { public Gui(){ HandlerClass handle = new HandlerClass(); setBorder(BorderFactory.createLineBorder(Color.black)); addKeyListener(handle); } int x = 30; int y = 30; public void paintComponent(Graphics g){ super.paintComponents(g); g.setColor(Color.BLUE); g.fillRect(x, y, 20, 20); } private class HandlerClass implements KeyListener{ public void keyTyped(KeyEvent e) { switch (e.getKeyChar()){ case 'w': repaint(x,y+1, 20,20); break; case 's': repaint(x,y-1, 20,20); System.out.println("testing if this fires"); break; } } public void keyPressed(KeyEvent e) { //todo } public void keyReleased(KeyEvent e) { //todo } } } </code></pre> <p>Any pointings in the right direction would be very helpful, thank you.</p>
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