Getting a Jlist to work

The code is supposed to activate a JList containg a label called hello as soon as the button is pressed.
Why does nothing happen when I click the activate-button?

Code:

---

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;

public class JListPractice extends JFrame implements ActionListener {

        JButton          activateButton        = new JButton("activate");
        JList                resultList                = new JList();
       
        public static void main(String[] args) {
                new JListPractice();
        }

        public JListPractice() {
               
                setTitle("");
                setBounds(200, 200, 500, 500);
                setDefaultCloseOperation(EXIT_ON_CLOSE);
                Container content = getContentPane();
               
                activateButton.addActionListener(this);
               
                content.add(activateButton, BorderLayout.NORTH);
                content.add(resultList, BorderLayout.CENTER);
               
                pack();
                setVisible(true);

        }
       
        @Override
        public void actionPerformed(ActionEvent ev) {
                if (ev.getSource() == activateButton){
                        System.out.println("searched");
                       
                        //String[] g = {"a", "b", "v"};
                        //for Characters.
                        resultList.add(new JLabel("Hello"));
                        //resultList = new JList(g);
                        //repaint();
                        getContentPane().add(resultList, BorderLayout.CENTER);
                }
               
        }

        private static final long serialVersionUID = 1L;
}

---

Well, you should not be adding "components" to the "list", you need to add "data" to the "model". So the first thing you need to do is use a ListModel that can be changed dynamically, such as the DefaultListModel. So you need to change:

Code:

---

//JList resultList = new JList();
JList resultList = new JList( new DefaultListModel());

---

Then you need to update the model:

Code:

---

// resultList.add(new JLabel("Hello"));
// getContentPane().add(resultList, BorderLayout.CENTER);
DefaultListModel model = (DefaultListModel)resultList.getModel();
model.addElement( "Hello" );
pack();

---

Read the JList API and follow the link to the Swing tutorial on "How to Use Lists" for working examples of using a JList. And download the entire tutorial for future reference.