import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import javax.swing.JComboBox; import javax.swing.JFrame; public class Main extends JFrame { JComboBox combo = new JComboBox(); public Main() { setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); combo.addItem("A"); combo.addItem("H"); combo.addItem("P"); combo.setEditable(true); System.out.println("#items=" + combo.getItemCount()); combo.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { System.out.println("Selected index=" + combo.getSelectedIndex() + " Selected item=" + combo.getSelectedItem()); } }); getContentPane().add(combo); pack(); setVisible(true); } public static void main(String arg[]) { new Main(); } }