个体工商户代办:滚动的小球 java源代码

//Checkers.java
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

//Checkers类
public class Checkers extends JFrame implements ActionListener {
//变量定义
CheckersPanel checkers = new CheckersPanel();
JButton startButton = new JButton("start");
JButton stopButton = new JButton("stop");
//构造函数
public Checkers(){
super("Checkers");
setSize(210,170);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel pane = new JPanel();
BorderLayout border = new BorderLayout();
pane.setLayout(border);
pane.add(checkers,"Center");

JPanel buttonPanel = new JPanel();
startButton.addActionListener(this);
buttonPanel.add(startButton);
stopButton.addActionListener(this);
stopButton.setEnabled(false);
buttonPanel.add(stopButton);

pane.add(buttonPanel,"South");
setContentPane(pane);
show();
}
//响应用户动作
public void actionPerformed(ActionEvent evt){
if(evt.getSource() == startButton){
checkers.playAnimation();
startButton.setEnabled(false);
stopButton.setEnabled(true);
}else{
checkers.stopAnimation();
startButton.setEnabled(true);
stopButton.setEnabled(false);
}
}
//主函数
public static void main(String[] arguments){
Checkers ck = new Checkers();
}
}

//CheckersPanel类
class CheckersPanel extends JPanel implements Runnable{
//变量定义
private Thread runner;
int xPos = 5;
int xMove = 4;
//播放动画
void playAnimation(){
if (runner ==null);{
runner = new Thread(this);
runner.start();
}
}
//停止动画
void stopAnimation(){
if (runner !=null);{
runner = null;
}
}
//运行
public void run(){
Thread thisThread = Thread.currentThread();
while(runner ==thisThread){
xPos += xMove;
if ((xPos > 105)|(xPos < 5))
xMove *= -1;
repaint();
try{
Thread.sleep(100);
}catch(InterruptedException e){}
}
}
//画图形
public void paintComponent(Graphics comp){
Graphics2D comp2D = (Graphics2D)comp;
comp2D.setColor(Color.blue);
comp2D.fillRect(0,0,100,100);
comp2D.setColor(Color.white);
comp2D.fillRect(100,0,100,100);
comp2D.setColor(Color.black);
comp2D.fillOval(xPos,5,90,90);
}
}

 
 
 
 
要制造那种效果只需要大约 30 行 Java 代码：

http://zhidao.baidu.com/question/5664286.html