Java Program using JCheckBox with ActionListener


In this program, You will learn how to implement JCheckBox with ActionListener in Java.


JCheckBox cb1, cb2, cb3;

public void actionPerformed(ActionEvent e) { }


Example: How to implement JCheckBox with ActionListener in Java

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JOptionPane;

class Test extends JFrame implements ActionListener {

    JButton jb1;
    JCheckBox cb1, cb2, cb3;

    Test() {

        cb1 = new JCheckBox("China");
        cb1.setBounds(50, 30, 150, 30);
        add(cb1);

        cb2 = new JCheckBox("India");
        cb2.setBounds(50, 60, 150, 30);
        add(cb2);

        cb3 = new JCheckBox("Aus");
        cb3.setBounds(50, 90, 150, 30);
        add(cb3);

        jb1 = new JButton("Click");
        jb1.setBounds(50, 200, 100, 30);
        add(jb1);

        jb1.addActionListener(this);

        setLayout(null);
        setSize(500, 500);
        setVisible(true);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        String country = "";

        if (cb1.isSelected()) {
            country = country + "China\n";
        }

        if (cb2.isSelected()) {
            country = country + "India\n";
        }

        if (cb3.isSelected()) {
            country = country + "Aus\n";
        }

        JOptionPane.showMessageDialog(this, country);

    }

    public static void main(String args[]) {
        Test t = new Test();
    }
}

Output:

Java JCheckBox