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Why won't the keyPressed method be called?

I am doing a fighting game in Java for a project and trying to get an image in order to move and repaint on a keyboard responsive panel (keyEvents). I am trying to accomplish this by switching the keyPressed method by adding keyListener to the panel. I gave an example in my Java book and code that I wrote in much the same way, but it just won't work.

What I'm really interested in is that it doesn't react at all to keyEvents. The program compiles everything and everything, but nothing happens. I have no idea what is going wrong. It does not reach the breakpoint in the method keyPressed()if I do this, and will not do println()it if I posted it. Thus, the method keyPressed()does not respond at all. I also tested and made sure that the panel is focusable, so I am sure that it has keyboard focus.

public class MovePanel extends JPanel implements KeyListener {
    private ImageIcon currentImage, facingLeft, facingRight;
    private int position;
    private final int MOVEMENT;
    private GameFrame gameFrame;
    private URL lefturl, righturl;

    public MovePanel(GameFrame gameFrame) {
        // Taking in a gameFrame to be able to swap the active panel 
        // (not really relevant).
        this.gameFrame = gameFrame;

        // Adding the key listener here.
        addKeyListener(this);

        // These are just the Images I'm using to test. 
        // Trying to get it to swap from one to the other.
    lefturl = getClass().getResource("/Images/facingLeft.jpg");
    righturl = getClass().getResource("/Images/facingRight.jpg");

    facingLeft = new ImageIcon(lefturl);
    facingRight = new ImageIcon(righturl);

    currentImage = facingLeft;
    position = 50;
    MOVEMENT = 30;

    setBackground(Color.red);
    setPreferredSize(new Dimension(600,300));

        // Calling this method so that the panel will react 
        // to the keyboard without having to be clicked.
    setFocusable(true);
    }

    // This is just the paintComponent method which works fine to paint the image
    // when starting the game.
    public void paintComponent(Graphics page) {
    super.paintComponent(page);
    currentImage.paintIcon(this, page, position, 170);
    }

    // No matter what I try to do inside the keyPressed method
    // it doesnt seem to react at all.
    public void keyPressed(KeyEvent e) {

        // This switch is to make the method react accordingly to the keys pressed.
        switch (e.getKeyCode()) {
        case KeyEvent.VK_LEFT: 

            // Here I'm changing the "active" image and the position 
            // by changing the position variable which is used 
            // to determine the x placement of the image.
            // This case is suppused to react if the left arrow key is pressed.
            currentImage = facingRight;
            position -= MOVEMENT;
            break; 
        case KeyEvent.VK_RIGHT: 
            currentImage = facingRight;
            position += MOVEMENT;
            break; 

        // This case is to exit to the menu when escape is pressed.
        case KeyEvent.VK_ESCAPE: 
            gameFrame.setMenuPanelActive();
            break; 
        }
        // After reacting to any of the proper keys pressed 
        // I'm trying to repaint which will use the
        // paintComponent method to paint the new image in its new position.
        repaint();
    }
    // I have empty definitions for the other 
    // implemented methods but won't be posting them.
}

Does anyone know why this is not working? Why keyPressed()won't the method respond?

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1 answer

I do not see the code as shown below

you should call the bottom line where u creates an instance of MovePanel

 MovePanel.requestFocus();      // Give the panel focus.



public class demo extends JFrame 
{
    MovePanel  panel;

    public demo () 
    {
        panel= new MovingTextPanel();
        this.getContentPane().setLayout(new BorderLayout())
        this.setTitle("Demo");
        this.pack();
        panel.requestFocus();      // Give the panel focus.
    }
}

MovePanel setFocusable true

 public MovePanel(GameFrame gameFrame) {

        this.setFocusable(true);   // Allow this panel to get focus.
        // Adding the key listener here.
        addKeyListener(this);


- Characters (a, A, #, ...) - handled in the keyTyped() listener.
- Virtual keys (arrow keys, function keys, etc) - handled with keyPressed() listener.
- Modifier keys (shift, alt, control, ...) - Usually their status (up/down) is tested by calls in one of the other listeners, rather than in keyPressed().

  public void keyTyped(KeyEvent e) {
    System.out.println(e.toString());
  }
  public void keyPressed(KeyEvent e) {
   System.out.println(e.toString());
  }
  public void keyReleased(KeyEvent e) {
    System.out.println(e.toString());
  }
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