Question

JAVA 键盘监听

package Anime;

import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.image.ImageObserver;

public class Sample extends Frame {

private Image img = null;
private Image img2 = null;
private Image img3 = null;
int by=30;

public static void main(String[] args){
new Sample().setVisible(true);
}

public Sample(){
setSize(803,603);

img = Toolkit.getDefaultToolkit().createImage("22.gif");
img3 = Toolkit.getDefaultToolkit().createImage("231.gif");
img2 = Toolkit.getDefaultToolkit().createImage("3.jpg");

this.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent ev){
System.exit(0);
}
});

this.addKeyListener(new KeyAdapter(){
public void keyPressed(KeyEvent e){

if((KeyEvent.VK_RIGHT)!=0)
by = by+5;

}
});
}

public void update(Graphics g){
paint(g);
}

public void paint(Graphics g){

g.drawImage(img2,0,0,this);
g.drawImage(img3,by,490,this);
g.drawImage(img,580,260,this);
}

public boolean imageUpdate(Image im,int flag,int x,int y,int w,int h){
super.imageUpdate(im,flag,x,y,w,h);

return true;
}
}
这个代码想实现游戏角色的左右移动 但是现在只能实现向右移动，并且按方向左键角色还是向右移动，请教解决办法

Answer 1

this.addKeyListener(new KeyAdapter(){
public void keyPressed(KeyEvent e){
if(e.getKeyCode()==KeyEvent.VK_RIGHT)
by = by+5;
else if(e.getKeyCode()==KeyEvent.VK_LEFT)
by = by-5;
}
});
这里这样改就ok了，不过你这个程序还有好多问题呢。
public void paint(Graphics g){

g.drawImage(img2,0,0,this);
g.drawImage(img3,by,490,this);
g.drawImage(img,580,260,this);
repaint();
}
这里面还要加一个repaint();方法，要不看不出移动的，问题太多改不完，你问的问题我算是解决了，嘿嘿，给分吧，有什么问题可以hi我。

Answer 2

if((KeyEvent.VK_RIGHT)!=0)是不对的

应该改成 if(evt.getKeyCode()==KeyEvent.VK_RIGHT)

Answer 3

那人物怎么放大缩小呢？