JRadioButtonItemListener.java Source code

Introduction

Here is the source code for JRadioButtonItemListener.java

Source

import java.awt.GridLayout;
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.JPanel;
import javax.swing.JRadioButton;

public class JRadioButtonItemListener {
    public static void main(String args[]) {
        JFrame frame = new JFrame("Grouping Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JPanel panel = new JPanel(new GridLayout(0, 1));

        ButtonGroup group = new ButtonGroup();
        JRadioButton aRadioButton = new JRadioButton("A");
        JRadioButton bRadioButton = new JRadioButton("B");

        ItemListener itemListener = new ItemListener() {
            String lastSelected;

            public void itemStateChanged(ItemEvent itemEvent) {
                AbstractButton aButton = (AbstractButton) itemEvent.getSource();
                int state = itemEvent.getStateChange();
                String label = aButton.getText();
                String msgStart;
                if (state == ItemEvent.SELECTED) {
                    if (label.equals(lastSelected)) {
                        msgStart = "Reselected -> ";
                    } else {
                        msgStart = "Selected -> ";
                    }
                    lastSelected = label;
                } else {
                    msgStart = "Deselected -> ";
                }
                System.out.println(msgStart + label);
            }
        };

        panel.add(aRadioButton);
        group.add(aRadioButton);
        panel.add(bRadioButton);
        group.add(bRadioButton);

        aRadioButton.addItemListener(itemListener);
        bRadioButton.addItemListener(itemListener);

        frame.add(panel);
        frame.setSize(300, 200);
        frame.setVisible(true);
    }

}