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();
}
}
}

}