Event Handling using Inner Class in Applet

We can handle the Event in Applet, AWT or Swing by following three different methods:

• Inner Class
• Anonymous class
• this Pointer

In this example, i will show you that how to use inner classes to handle the events in Applet.

package com.kunal.applet;

import java.applet.Applet;
import java.awt.Button;
import java.awt.TextField;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class InerClassButton extends Applet {

 TextField txtSource;
 Button btnLower,btnUpper;
 String lowerText="lower case";

  public void init()
  {
     txtSource=new TextField(20);
     btnLower=new Button(lowerText);
     btnUpper=new Button("upper case");

     btnLower.addActionListener(new MyActionListener());
     btnUpper.addActionListener(new MyActionListener());

     add(txtSource);
     add(btnLower);
     add(btnUpper);
   }
   class MyActionListener implements ActionListener
   {
    @Override
     public void actionPerformed(ActionEvent evt) {
     String tmp=txtSource.getText();
     txtSource.setText(evt.getActionCommand()==lowerText?tmp.toLowerCase():tmp.toUpperCase());
     }
   }
}