使用鼠標在面板上移動消息

“`
import java.awt.*;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionAdapter;

import javax.swing.JFrame;
import javax.swing.JPanel;

public class Loan extends JFrame
{
public Loan()
{
MovableMessagePanel p=new MovableMessagePanel(“Welcom to 306”);

        setLayout(new BorderLayout());
add(p); 
}

public static void main(String[] args)
{
Loan frame=new Loan();
frame.setTitle(“Loan”);
frame.setSize(200,100);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}

static class MovableMessagePanel extends JPanel
{
private String message=”Werlcom to java”;
private int x=20;
private int y=20;

public MovableMessagePanel(String s)
{
    message =s;
    addMouseMotionListener(

new MouseMotionAdapter()
{
public void mouseDragged(MouseEvent e)
{
x=e.getX();
y=getY();
repaint();
}
});//注意分號。

}
protected void paintComponent(Graphics g)
{
super.paintComponent(g);
g.drawString(message,x,y);
}
}

}

“`