键盘事件处理程序

import java.awt.*;
import java.applet.*;
import java.awt.event.*;
public class keyevent extends Applet
{
Color c;
Label lb = new Label("轮流输入R,G,B,Y,O,W,P键，可改变背景颜色");
TextField tf = new TextField(10);
public void init()
{
setLayout(new FlowLayout(FlowLayout.CENTER,0,0));
add(lb);
add(tf);
tf.addKeyListener(new koListener());
}
class koListener extends KeyAdapter
{
public void keyTyped(KeyEvent e){}
public void keyPressed (KeyEvent e)
{
c = Color.red;
if (e.getKeyChar()=='r')
c = Color.red;
else if (e.getKeyChar()=='g')
c = Color.green;
else if (e.getKeyChar()=='b')
c = Color.blue;
else if (e.getKeyChar()=='y')
c = Color.yellow;
else if (e.getKeyChar()=='o')
c = Color.orange;
else if (e.getKeyChar()=='w')
c = Color.white;
else if (e.getKeyChar()=='p')
c = Color.pink;
setBackground(c);
}
public void keyReleased(KeyEvent e){}
}

}