SimpleButtonGroupExample.java Source code

Introduction

Here is the source code for SimpleButtonGroupExample.java

Source

/*
Java Swing, 2nd Edition
By Marc Loy, Robert Eckstein, Dave Wood, James Elliott, Brian Cole
ISBN: 0-596-00408-7
Publisher: O'Reilly 
*/
// SimpleButtonGroupExample.java
//A ButtonGroup voting booth.
//

import java.awt.Container;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;

import javax.swing.AbstractButton;
import javax.swing.ButtonGroup;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JRadioButton;

public class SimpleButtonGroupExample {

    public static void main(String[] args) {
        // Some choices
        JRadioButton choice1, choice2, choice3;
        choice1 = new JRadioButton("Bach: Well Tempered Clavier, Book I");
        choice1.setActionCommand("bach1");
        choice2 = new JRadioButton("Bach: Well Tempered Clavier, Book II");
        choice2.setActionCommand("bach2");
        choice3 = new JRadioButton("Shostakovich: 24 Preludes and Fugues");
        choice3.setActionCommand("shostakovich");

        // A group, to ensure that we only vote for one.
        final ButtonGroup group = new ButtonGroup();
        group.add(choice1);
        group.add(choice2);
        group.add(choice3);

        // A simple ActionListener, showing each selection using the ButtonModel
        class VoteActionListener implements ActionListener {
            public void actionPerformed(ActionEvent ev) {
                String choice = group.getSelection().getActionCommand();
                System.out.println("ACTION Choice Selected: " + choice);
            }
        }

        // A simple ItemListener, showing each selection and deselection
        class VoteItemListener implements ItemListener {
            public void itemStateChanged(ItemEvent ev) {
                boolean selected = (ev.getStateChange() == ItemEvent.SELECTED);
                AbstractButton button = (AbstractButton) ev.getItemSelectable();
                System.out
                        .println("ITEM Choice Selected: " + selected + ", Selection: " + button.getActionCommand());
            }
        }

        // Add listeners to each button
        ActionListener alisten = new VoteActionListener();
        choice1.addActionListener(alisten);
        choice2.addActionListener(alisten);
        choice3.addActionListener(alisten);

        ItemListener ilisten = new VoteItemListener();
        choice1.addItemListener(ilisten);
        choice2.addItemListener(ilisten);
        choice3.addItemListener(ilisten);

        // Throw everything together
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        Container c = frame.getContentPane();
        c.setLayout(new GridLayout(0, 1));
        c.add(new JLabel("Vote for your favorite prelude & fugue cycle"));
        c.add(choice1);
        c.add(choice2);
        c.add(choice3);
        frame.pack();
        frame.setVisible(true);
    }
}