碰壁球

来源：互联网发布：安卓版外国网络电视apk 编辑：程序博客网时间：2024/04/27 16:04

package 碰壁球;
import java.applet.*;
import java.awt.*;
public class UsedoubleBuffer extends Applet implements Runnable{
int X,Y,moveX,moveY,width,height;
Image offI;
Graphics offG;
Thread thread;
public void init()
{
  X=0;        //X Y轴
  Y=0;
  moveX=2;    //移动距离
  moveY=3;
  setSize(500,450);
  width=getSize().width;
  height=getSize().height;
  offI=createImage(width,height);
  offG=offI.getGraphics();
}
public void start()
{
  if(thread==null)
  {
   thread=new Thread(this);
   thread.start();
  }
}
public void stop()
{
  thread=null;
}
public void update(Graphics g)
{
  paint(g);
}
public void paint(Graphics g)
{
  offG.setColor(Color.black);        //清除子画面
  offG.fillRect(0, 0, width, height);
  offG.setColor(Color.white);
  offG.fillOval(X, Y, 30, 30);

  g.drawImage(offI, 0, 0, this);
}
public void run()
{
  while(true)
  {
   repaint();
   try{
    Thread.sleep(10);
   }
   catch(InterruptedException e){}
   X=X+moveX;
   Y=Y+moveY;
   if(X>=width-30)
    moveX=-moveX;
   if(X<=0)
    moveX=-moveX;
   if(Y>=height-30)
    moveY=-moveY;
   if(Y<=0)
    moveY=-moveY;
  }
}

}