title: Adding an image to a null layout jpanel
body: <p>I am looking to add a JPEG image of Pacman to a null layout JPanel so that I can use a key listener to move the image. Here's the code I have so far:</p>
  
  <pre><code>import java.awt.*;
  import java.awt.event.*;
  import javax.swing.*;
  import javax.imageio.*;
  import java.awt.image.*;
  import java.io.*;
  
  public class PacmanCharacterMovement2{
    static BufferedImage pacman;
    static int xCoor;
    static int yCoor;
    public static class PacmanPanel extends JPanel implements KeyListener {
      public void paintComponent(Graphics g) {
          super.paintComponent(g);
          g.drawImage(pacman, xCoor, yCoor, null);
      }
      public void keyTyped(KeyEvent e) {
      }
      public void keyPressed(KeyEvent e) {
        if (e.getKeyCode() == KeyEvent.VK_UP) {
          xCoor = xCoor--;
          yCoor = yCoor;
        }
        else if (e.getKeyCode() == KeyEvent.VK_DOWN) {
          xCoor = xCoor++;
          yCoor = yCoor;        
        }
        else if (e.getKeyCode() == KeyEvent.VK_LEFT) {
          xCoor = xCoor;
          yCoor = yCoor--;      
        }
        else if (e.getKeyCode() == KeyEvent.VK_RIGHT) {
          xCoor = xCoor;
          yCoor = yCoor++;        
        }
        else{}
        repaint();
      }
      public void keyReleased(KeyEvent e) {
      }
    }
    public static void main(String[] agrs){
      try {
        pacman = ImageIO.read(new File("PacmanCharacter2.jpg"));
      } catch (IOException e) {}
      xCoor = 30;
      yCoor = 30;
      JFrame window = new JFrame ("Pacman Movement");
      JPanel pacmanPanel = new JPanel ();
      pacmanPanel.setLayout(null);
  
      PacmanPanel mainPanel = new PacmanPanel();
  
      window.setContentPane(mainPanel);
      window.setSize(600,450);
      window.setLocation(350,150);
      window.setVisible(true); 
    }                                                           
  }
  </code></pre>
  
  <p>The image appears on the screen but it does not move.</p>