KeyEvent Handling Problem

Danish Kamran

Hi

I've wite a coden for handling key event but it is't work properly.The problem is each time I press any key it throws some kind of execption. Well
I don't know, why this happening. Kindly help me in this regard. The code isa shown below

import javax.swing.*;
import java.awt.event.*;
import java.awt.*;

public class Screen implements KeyListener
{
private Tray T; // Class for drawing rectangle at specific position
public Screen()
{
Tray T = new Tray(30 , 7);
JFrame f = new JFrame("KeyEventHandling");
Container c = f.getContentPane();
c.add(T);
f.setSize(500 , 500);
f.setVisible(true);
f.addKeyListener(this);
f.setDefaultCloseOperation(f.EXIT_ON_CLOSE);
}
public static void main(String []args)
{
Screen S = new Screen();

}
public void keyPressed(KeyEvent e)
{
System.out.println("Helloooooo "+e.getKeyText( e.getKeyCode() )); // for debugging purpose
T.setX();
T.repaint();
}
public void keyTyped(KeyEvent e)
{
System.out.println("Helloooooo "+e.getKeyTex(e.getKeyCode() )); // for debugging purpose
T.setX();
T.repaint();
}
public void keyReleased(KeyEvent e)
{
System.out.println("Helloooo "+e.getKeyText( e.getKeyCode() ));
T.setX();
T.repaint();
}
}


whenever I press any key The methods of class Tray Isn't call and execption in thrown on Command Prompt

zibadian

: Hi
:
: I've wite a coden for handling key event but it is't work
: properly.The problem is each time I press any key it throws some
: kind of execption. Well
: I don't know, why this happening. Kindly help me in this regard. The
: code isa shown below
:
: import javax.swing.*;
: import java.awt.event.*;
: import java.awt.*;
:
: public class Screen implements KeyListener
: {
: private Tray T; // Class for drawing rectangle at specific position
: public Screen()
: {
: Tray T = new Tray(30 , 7);
: JFrame f = new JFrame("KeyEventHandling");
: Container c = f.getContentPane();
: c.add(T);
: f.setSize(500 , 500);
: f.setVisible(true);
: f.addKeyListener(this);
: f.setDefaultCloseOperation(f.EXIT_ON_CLOSE);
: }
: public static void main(String []args)
: {
: Screen S = new Screen();
:
: }
: public void keyPressed(KeyEvent e)
: {
: System.out.println("Helloooooo "+e.getKeyText( e.getKeyCode()
: )); // for debugging purpose
: T.setX();
: T.repaint();
: }
: public void keyTyped(KeyEvent e)
: {
: System.out.println("Helloooooo "+e.getKeyTex(e.getKeyCode() ));
: // for debugging purpose
: T.setX();
: T.repaint();
: }
: public void keyReleased(KeyEvent e)
: {
: System.out.println("Helloooo "+e.getKeyText( e.getKeyCode() ));
: T.setX();
: T.repaint();
: }
: }
:
:
: whenever I press any key The methods of class Tray Isn't call and
: execption in thrown on Command Prompt
:
What is the exception you get? And in which situation do you get that exception?