SWING - WindowListener Interface
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
| Sr.No. | 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 a 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:/ > SWING > com > tutorialspoint > gui >
SwingListenerDemo.java
package com.tutorialspoint.gui;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class SwingListenerDemo {
private JFrame mainFrame;
private JLabel headerLabel;
private JLabel statusLabel;
private JPanel controlPanel;
private JFrame aboutFrame;
public SwingListenerDemo(){
prepareGUI();
}
public static void main(String[] args){
SwingListenerDemo swingListenerDemo = new SwingListenerDemo();
swingListenerDemo.showWindowListenerDemo();
}
private void prepareGUI(){
mainFrame = new JFrame("Java SWING Examples");
mainFrame.setSize(400,400);
mainFrame.setLayout(new GridLayout(3, 1));
headerLabel = new JLabel("",JLabel.CENTER );
statusLabel = new JLabel("",JLabel.CENTER);
statusLabel.setSize(350,100);
mainFrame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent windowEvent){
System.exit(0);
}
});
controlPanel = new JPanel();
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");
JButton okButton = new JButton("OK");
aboutFrame = new JFrame();
aboutFrame.setSize(300,200);;
aboutFrame.setTitle("WindowListener Demo");
aboutFrame.addWindowListener(new CustomWindowListener());
JPanel panel = new JPanel();
panel.setBackground(Color.white);
JLabel msglabel = new JLabel("Welcome to TutorialsPoint SWING Tutorial."
,JLabel.CENTER);
panel.add(msglabel);
aboutFrame.add(panel);
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 the command prompt. Go to D:/ > SWING and type the following command.
D:\SWING>javac com\tutorialspoint\gui\SwingListenerDemo.java
If no error occurs, it means the compilation is successful. Run the program using the following command.
D:\SWING>java com.tutorialspoint.gui.SwingListenerDemo
Verify the following output.