windowlistenerdemo.java

《java事件处理指南》一书的代码,好东西

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

public class WindowListenerDemo extends JFrame 
                                 implements WindowListener
{
   private JFrame frame1, frame2;
   private JTextField jtf;

   public WindowListenerDemo()
   {
/*  A secondary JFrame is created and made visible.  The frame  */
/*  registers a WindowListener.                                 */

      frame1 = new JFrame("Child Window");
      frame1.setBounds(400, 150, 200, 100);
      frame1.setVisible(true);
      frame1.addWindowListener(this);

      jtf = new JTextField(20);
      jtf.setEditable(false);

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

      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      setBounds(100, 100, 300, 200);
      setVisible(true);
   }

/*  The WindowListenerDemo class serves as the WindowListener so   */
/*  it must provide implementation of the methods declared in the  */
/*  WindowListener interface.  These methods are written so as to  */
/*  indicate the status of the child frame.                        */

   public void windowActivated(WindowEvent event)
   {
      jtf.setText("Child window now active");
   }

   public void windowClosed(WindowEvent event)
   {
      jtf.setText("Child window closed");
   }

   public void windowClosing(WindowEvent event)
   {
      jtf.setText("Child window closing");
   }

   public void windowDeactivated(WindowEvent event)
   {
      jtf.setText("Child window no longer active");
   }

   public void windowDeiconified(WindowEvent event)
   {
      jtf.setText("Child window de-iconified");
   }

   public void windowIconified(WindowEvent event)
   {
      jtf.setText("Child window iconified");
   }

   public void windowOpened(WindowEvent event)
   {
      jtf.setText("Child window opened");
   }

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