// Demonstrating the ItemListener  
 


 

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.GridLayout;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;

import javax.swing.ButtonGroup;
import javax.swing.JComboBox;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JRadioButton;

public class ItemTest {
  public static void main(String args[]) {
    JFrame frame = new JFrame();
    Container contentPane = frame.getContentPane();

    ItemListener listener = new ItemListener() {
      public void itemStateChanged(ItemEvent e) {
        System.out.println("Source: " + name(e.getSource()));
        System.out.println("Item: " + name(e.getItem()));
        int state = e.getStateChange();
        System.out.println("State: "
            + ((state == ItemEvent.SELECTED) ? "Selected"
                : "Deselected"));
      }

      private String name(Object o) {
        if (o instanceof JComponent) {
          JComponent comp = (JComponent) o;
          return comp.getName();
        } else {
          return o.toString();
        }
      }
    };

    JPanel panel = new JPanel(new GridLayout(0, 1));
    ButtonGroup group = new ButtonGroup();
    JRadioButton option = new JRadioButton("French Fries", true);
    option.setName(option.getText());
    option.addItemListener(listener);
    group.add(option);
    panel.add(option);
    option = new JRadioButton("Onion Rings", false);
    option.setName(option.getText());
    option.addItemListener(listener);
    group.add(option);
    panel.add(option);
    option = new JRadioButton("Ice Cream", false);
    option.setName(option.getText());
    option.addItemListener(listener);
    group.add(option);
    panel.add(option);
    contentPane.add(panel, BorderLayout.NORTH);

    String flavors[] = { "Item 1", "Item 2", "Item 3"};
    JComboBox jc = new JComboBox(flavors);
    jc.setName("Combo");
    jc.addItemListener(listener);
    jc.setMaximumRowCount(4);
    contentPane.add(jc, BorderLayout.SOUTH);

    frame.pack();
    frame.show();
  }
}