mmlistenerdemo.java

来自「《java事件处理指南》一书的代码,好东西」· Java 代码 · 共 53 行

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

public class MMListenerDemo extends JFrame
{
   private JTextField jtf;

   public MMListenerDemo()
   {
      jtf = new JTextField(20);
      jtf.setEditable(false);

/*  A Panel registers a MouseMotionHandler and is added  */
/*  to a JFrame.                                         */

      JPanel panel = new JPanel();
      panel.addMouseMotionListener(new MouseMotionHandler());
      panel.setBackground(Color.yellow);

      getContentPane().add(panel, BorderLayout.CENTER);
      getContentPane().add(jtf, BorderLayout.SOUTH);

      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      setBounds(100, 100, 200, 200);
      setVisible(true);
   }

/*  The MouseMotionListener is implemented as an inner class.      */
/*  Whenever the mouse is moved or dragged within the bounding     */
/*  area of the JPanel, MouseEvents are generated and sent to      */
/*  the MouseMotionListener.  The JTextField at the bottom of      */
/*  the JFrame is updated with the current position of the mouse.  */

   class MouseMotionHandler implements MouseMotionListener
   {
      public void mouseMoved(MouseEvent event)
      {
         jtf.setText("mouse moved to "+event.getX()+","+event.getY());
      }

      public void mouseDragged(MouseEvent event)
      {
         jtf.setText("mouse dragged to "+event.getX()+","+event.getY());
      }
   }

   public static void main(String args[])
   {
      MMListenerDemo demo = new MMListenerDemo();
   }
}