JList:addListSelectionListener(ListSelectionListener l)

JList:addListSelectionListener(ListSelectionListener l)

To determine if elements in a JList have been selected,you have to add JList:addListSelectionListener
Previous post we added ActionListener to JList

JList:addListSelectionListener Example

[

import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JScrollPane;
import javax.swing.UIManager;

import java.util.ArrayList;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;

import javax.swing.JLabel;
import javax.swing.JButton;

public class JListExample extends JFrame implements ListSelectionListener{
    public JList<String> list;
    public JLabel label;
    JListExample()
    {
        super("JFrame Example");
        try        {
            UIManager.setLookAndFeel

("com.sun.java.swing.plaf.windows.WindowsClassicLookAndFeel");
        }
        catch(Exception e)
        {

        }
        ArrayList arr=new ArrayList();
        arr.add("Java");
        arr.add("C#");
        arr.add("C++");

        list=new JList(arr.toArray());
        list.setBounds(50, 50, 100, 100);
        add(list);
        list.addListSelectionListener(this);

        setSize(400,400);
        setLayout(null);
        setLocationRelativeTo(null);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setVisible(true);
    }
    public void valueChanged(ListSelectionEvent event)
    {
        if(event.getValueIsAdjusting())
            return;

        System.out.println("Value changed from " +event.getLastIndex() + 

" to " +event.getFirstIndex());

    }
    public static void main(String args[])
    {
        new JListExample();
    }

}

]

JList:addListSelectionListener Output

Below Code sets Application look and feel to WindowsClassicLookAndFeel
[

 try        {
            UIManager.setLookAndFeel

("com.sun.java.swing.plaf.windows.WindowsClassicLookAndFeel");
        }
        catch(Exception e)
        {

]

 setDefaultCloseOperation(EXIT_ON_CLOSE) ensures the application exits when the

 close button is clicked

See also : Java JTable