上一节实现了满天星的效果,本节将实现滚雪球的小实例,这里要用到重绘和线程的知识,代码如下:
import java.awt.Color;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Panel;
public class SnowBall {
	public static void main(String[] args) {
		Frame frame=new Frame();
		frame.setBackground(Color.BLACK);
		frame.setSize(1024, 768);
		
		MyPanel myPanel=new MyPanel();
		frame.add(myPanel);
		
		Thread thread=new Thread(myPanel);
		thread.start();
		frame.show();
	}
}
class MyPanel extends Panel implements Runnable{
	int x=120;
	int y=10;
	@Override
	public void paint(Graphics g) {
		g.setColor(Color.WHITE);
		g.fillOval(x, y, 20, 20);
	}
	@Override
	public void run() {
		while (true) {
			y++;
			if(y>768){
				y=0;
			}
			repaint();
			
		}
		
		
		
	}
	
}try {
				Thread.sleep(10);
			} catch (InterruptedException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}原文:http://blog.csdn.net/yayun0516/article/details/50807756