AWT ActionListener Interface

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The class which processes the ActionEvent should implement this interface.The object of that class must be registered with a component. The object can be registered using the addActionListener() method. When the action event occurs, that object's actionPerformed method is invoked.

Interface declaration

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

public interface ActionListener
   extends EventListener

Interface methods

S.N.Method & Description
1void actionPerformed(ActionEvent e)
Invoked when an action occurs.

Methods inherited

This interface inherits methods from the following interfaces:

  • java.awt.EventListener

ActionListener 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.showActionListenerDemo();
   }

   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 showActionListenerDemo(){
      headerLabel.setText("Listener in action: ActionListener");      

      ScrollPane panel = new ScrollPane();      
      panel.setBackground(Color.magenta);            

      Button okButton = new Button("OK");

      okButton.addActionListener(new CustomActionListener());        
      panel.add(okButton);
      controlPanel.add(panel);

      mainFrame.setVisible(true); 
   }

   class CustomActionListener implements ActionListener{

      public void actionPerformed(ActionEvent e) {
         statusLabel.setText("Ok Button Clicked.");
      }
   }
}

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 ActionListener

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