ball.java

小球游戏的源代码 一个简单的小游戏包括图形用户界面

import java.awt.*;
import javax.swing.*;
import javax.swing.event.*;
import java.awt.event.*;
import java.util.EventListener;
class MyPanel extends JPanel implements ActionListener,KeyListener
{
	private int x,y;
	private int xsteep=2;
	private int ysteep=2;
	
	private int xr=200;
	private int yr=400;
	private int rsteep=2;
	public JButton mb1=new JButton("开始");
	public JButton mb2=new JButton("停止");
	Timer t=new Timer(2,this);
	Timer t1=new Timer(2,this);
	MyPanel (){
		mb1.addActionListener(this);
		mb2.addActionListener(this);
		this.addKeyListener(this);
	}
	
	public void paintComponent(Graphics g)
	{
		
		Graphics2D g2d=(Graphics2D)g;
		super.paintComponent(g2d);
	    this.requestFocus(true);
    	g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
		g2d.setColor(Color.red);
		g2d.fillOval(x,y,20,20);
		g2d.setColor(Color.green);
		g2d.fillRect(xr,yr,100,20);
	}
	public void actionPerformed(ActionEvent e){
		if(e.getSource()==mb1)
			 t.start();
	   else if(e.getSource()==mb2)
		     t.stop();
		else if(e.getSource()==t)
		{
			x+=xsteep;
			y+=ysteep;
			
			//右
			if(x+20>=this.getWidth())
				xsteep=-xsteep;
			//左
			 if(x<=0)
				xsteep=-xsteep;
			//与挡板相撞
			 if((y==yr-20)&&(x>=xr-10)&&(x<=xr+90))
			 {
			 	ysteep=-ysteep;
//				   System.out.println ("yr="+yr);
//				   System.out.println ("xr="+xr);
			 }
			 //下
			  else if(y+20>=this.getHeight())
			 	 ysteep=-ysteep;
//			 else	
//			 {if(y+20>=this.getHeight())
//				ysteep=-ysteep;
//			 }
			 if(y<=0)
				ysteep=-ysteep;
			
			this.repaint();
		}
		else if(e.getSource()==t1)
		{
			 xr-=rsteep;
			 System.out.println ("xr="+xr);
			 if(xr<=0)
			 	 rsteep=-rsteep;
			 if(xr+100>=this.getWidth())
			 	rsteep=-rsteep;
			 	
			this.repaint();	
		}
	}
	public void keyTyped(KeyEvent e) {
	
	    
	}


	public void keyPressed(KeyEvent e) 
	{
	//	System.out.println (e.getKeyCode());
       
        	t1.start();
	}	 
	
	

	
	public void keyReleased(KeyEvent e) 
	{
		 t1.stop();
		
	}
}


public class Ball extends JFrame{  
    JPanel mpl=new JPanel();
    MyPanel  mp=new MyPanel();
    public Ball() {
    	this.setSize(500,500);
    	this.setLocation(60,20);
    	this.setDefaultCloseOperation(3);
    	mpl.add(mp.mb1);
    	mpl.add(mp.mb2);
    	mpl.setBackground(Color.gray);
    	this.add(mpl,"North");
    	this.add(mp);
    	this.setVisible(true);
    }
    public static void main (String[] args) {
    	new Ball();
    }

	
	
    
}