fork download
copy 
  1. import java.awt.Color;
  2. import java.awt.event.KeyAdapter;
  3. import java.awt.event.KeyEvent;
  4.  
  5. import javax.swing.JFrame;
  6. import javax.swing.JPanel;
  7.  
  8.  
  9. public class ListenerExample {
  10.  
  11.  
  12. 	public static void main(String[] args) {
  13. 		JFrame frame = new JFrame("Example");
  14. 		JPanel panel = new JPanel();
  15. 		frame.getContentPane().add(panel);
  16. 		frame.setVisible(true);
  17. 		panel.setVisible(true);
  18. 		panel.setSize(300, 300);
  19. 		frame.setSize(300, 300);
  20. 		frame.addKeyListener(new KeyListener(panel));
  21.  
  22.  
  23. 	}
  24.  
  25. 	private static class KeyListener extends KeyAdapter{
  26. 		private JPanel panel;
  27.  
  28. 	    public KeyListener(JPanel panel1) {
  29. 			panel = panel1;	
  30. 		}
  31.  
  32. 		public void keyPressed(KeyEvent e) {
  33. 	       char ch = e.getKeyChar();
  34. 	       int code = e.getKeyCode();
  35. 	       if (ch == 'a'){  
  36. 	    	   panel.setBackground(Color.red);
  37. 	       }   
  38. 	       if (ch == 's'){  
  39. 	    	   panel.setBackground(Color.yellow);
  40. 	       } 
  41. 	       if (ch == 'd'){  
  42. 	    	   panel.setBackground(Color.blue);
  43. 	       } 
  44. 	       panel.repaint();
  45. 	    }
  46. 	}
  47. }
Compilation error #stdin compilation error #stdout 0s 0KB
comments (?)
stdin
copy 
Standard input is empty
compilation info 
Main.java:9: error: class ListenerExample is public, should be declared in a file named ListenerExample.java
public class ListenerExample {
       ^
1 error
stdout
copy 
Standard output is empty
https://ideone.com/CtDgCA
language:
Java (12.0.1)
created:
11 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!