请教 这段程序 键盘监听 怎么无效?谢谢
请教 这段程序 键盘监听 怎么无效?谢谢
import java.applet.Applet;
import java.awt.Graphics;
import java.awt.event.*;
public class TestKeyListener extends Applet implements KeyListener {
int x=20;
public void init() {
addKeyListener(this);
}
public void paint(Graphics g){
//g.drawString("x is "+x,x,40) ;
g.drawString("A",x,40) ;
}
public void keyTyped(KeyEvent e) {
if(e.getKeyChar()=='r'||e.getKeyChar()=='R'){
x += 20;
repaint();
}
}
public void keyReleased( KeyEvent e ) {}
public void keyPressed( KeyEvent e ) {}
}
<applet code=TestKeyListener.class width=400 height=200>
</applet>
import java.applet.Applet;
import java.awt.Graphics;
import java.awt.event.*;
public class TestKeyListener extends Applet implements KeyListener {
int x=20;
public void init() {
addKeyListener(this);
}
public void paint(Graphics g){
//g.drawString("x is "+x,x,40) ;
g.drawString("A",x,40) ;
}
public void keyTyped(KeyEvent e) {
if(e.getKeyChar()=='r'||e.getKeyChar()=='R'){
x += 20;
repaint();
}
}
public void keyReleased( KeyEvent e ) {}
public void keyPressed( KeyEvent e ) {}
}
<applet code=TestKeyListener.class width=400 height=200>
</applet>
...全文


Java SE
