AWT WindowListener Interface


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The class which processes the WindowEvent should implement this interface.The object of that class must be registered with a component. The object can be registered using the addWindowListener() method.

Interface declaration

Following is the declaration for java.awt.event.WindowListener interface:

public interface WindowListener
   extends EventListener

Interface methods

S.N.Method & Description
1

void windowActivated(WindowEvent e)

Invoked when the Window is set to be the active Window.

2

void windowClosed(WindowEvent e)

Invoked when a window has been closed as the result of calling dispose on the window.

3

void windowClosing(WindowEvent e)

Invoked when the user attempts to close the window from the window's system menu.

4

void windowDeactivated(WindowEvent e)

Invoked when a Window is no longer the active Window.

5

void windowDeiconified(WindowEvent e)

Invoked when a window is changed from a minimized to a normal state.

6

void windowIconified(WindowEvent e)

Invoked when a window is changed from a normal to a minimized state.

7

void windowOpened(WindowEvent e)

Invoked the first time a window is made visible.

Methods inherited

This interface inherits methods from the following interfaces:

  • java.awt.EventListener

WindowListener Example

Create the following java program using any editor of your choice in say D:/ > AWT > com > tutorialspoint > gui >

AwtListenerDemo.java
package com.tutorialspoint.gui;

import java.awt.*;
import java.awt.event.*;

public class AwtListenerDemo {
   private Frame mainFrame;
   private Label headerLabel;
   private Label statusLabel;
   private Panel controlPanel;

   public AwtListenerDemo(){
      prepareGUI();
   }

   public static void main(String[] args){
      AwtListenerDemo  awtListenerDemo = new AwtListenerDemo();  
      awtListenerDemo.showWindowListenerDemo();
   }

   private void prepareGUI(){
      mainFrame = new Frame("Java AWT Examples");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
            System.exit(0);
         }        
      });    
   
      headerLabel = new Label();
      headerLabel.setAlignment(Label.CENTER);
      statusLabel = new Label();        
      statusLabel.setAlignment(Label.CENTER);
      statusLabel.setSize(350,100);

      controlPanel = new Panel();
      controlPanel.setLayout(new FlowLayout());

      mainFrame.add(headerLabel);
      mainFrame.add(controlPanel);
      mainFrame.add(statusLabel);
      mainFrame.setVisible(true);  
   }

   private void showWindowListenerDemo(){
      headerLabel.setText("Listener in action: WindowListener");      

      Button okButton = new Button("OK");

      aboutFrame = new Frame();
      aboutFrame.setSize(300,200);;
      aboutFrame.setTitle("WindowListener Demo");
      aboutFrame.addWindowListener(new CustomWindowListener());

      Label msgLabel = new Label("Welcome to tutorialspoint.");
      msgLabel.setAlignment(Label.CENTER);
      msgLabel.setSize(100,100);
      aboutFrame.add(msgLabel);
      aboutFrame.setVisible(true);
   }

   class CustomWindowListener implements WindowListener {
      public void windowOpened(WindowEvent e) {
      }

      public void windowClosing(WindowEvent e) {
         aboutFrame.dispose();      
      }
      
      public void windowClosed(WindowEvent e) {
      }

      public void windowIconified(WindowEvent e) {
      }

      public void windowDeiconified(WindowEvent e) {
      }

      public void windowActivated(WindowEvent e) {
      }

      public void windowDeactivated(WindowEvent e) {
      }
   }   
}

Compile the program using command prompt. Go to D:/ > AWT and type the following command.

D:\AWT>javac com\tutorialspoint\gui\AwtListenerDemo.java

If no error comes that means compilation is successful. Run the program using following command.

D:\AWT>java com.tutorialspoint.gui.AwtListenerDemo

Verify the following output

AWT WindowListener
awt_event_listeners.htm

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