使用Timer类的动画

程序清单

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

public class AnimationDemo extends JFrame {

public AnimationDemo(){    add(new MovingMessagepanel("Message  moving"));}public static void main(String[] args){    AnimationDemo frame=new AnimationDemo();    frame.setTitle("AnimationDemo");    frame.setSize(280,100);    frame.setLocationRelativeTo(null);    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);    frame.setVisible(true);}static class MovingMessagepanel extends JPanel{    private String message ="Welcome to Java";    private int xCoordinate=0;    private int yCoordinate=20;    public   MovingMessagepanel(String message)    {        this.message=message;         Timer timer = new Timer(1000, new TimerListener());        timer.start();    }    public  void paintComponent(Graphics g)    {        super.paintComponent( g);        if(xCoordinate>getWidth())        {            xCoordinate=-20;        }        xCoordinate += 20;         g.drawString(message,xCoordinate,yCoordinate);    }    class TimerListener implements ActionListener    {        public void actionPerformed(ActionEvent e)        {            repaint();        }    }}

}