How to handle action event for JComboBox in Java?

The following is an example to handle action event for JComboBox in Java:

Example

import java.awt.BorderLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JComboBox; import javax.swing.JFrame; public class SwingDemo {    public static void main(String[] args) throws Exception {       JFrame frame = new JFrame();       frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);       JComboBox<String> combo = new JComboBox<>(new String[] { "One","Two", "Three","Four","Five", "Six" });       JButton add = new JButton("Add");       add.addActionListener(new ActionListener() {          @Override          public void actionPerformed(ActionEvent e) {             combo.addItem("New");          }       });       frame.add(combo);       frame.add(add, BorderLayout.NORTH);       frame.setSize(500, 100);       frame.setVisible(true);    } }

Output

Now, we have the following items:

Now, click “Add” above to add a new item on runtime. After clicking, a new item would be visible in the bottom as shown in the following screenshot: