Re: JComboBox with DefaultComboBoxModel doesn't allow to add or remove

On 11/22/2012 4:03 AM, Rotariu Mihai wrote:


That doesn't really cut it as an SSCCE because it doesn't compile. But
I was intrigued enough to write one for you.

import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import javax.swing.text.*;

public class test extends JPanel {
     static final String[] items = {
"one","two","three","four","five","six" };

     private final Vector<String> vector = new Vector<>();
     private final JComboBox<String> box;

     public test() {
         box = new JComboBox<String>(vector);
         box.setEditable(true);
         for (String item: items)
             box.addItem(item);
         box.addActionListener(new ActionListener() {
             public void actionPerformed(ActionEvent ae) {
                 String item = (String)box.getSelectedItem();
                 // if item is not in list and item is not empty
                 if (!vector.contains(item) && !item.equals("")) {
                     box.addItem(item);
                     // attempt to blank entry field
                     Component c = box.getEditor().getEditorComponent();
                     if (c instanceof JTextComponent)
                         ((JTextComponent)c).setText("");
                 }
             }
         });

         JButton rem = new JButton("Remove All");
         rem.addActionListener(new ActionListener() {
             public void actionPerformed(ActionEvent ae) {
                 vector.removeAllElements();
                 Component c = box.getEditor().getEditorComponent();
                 if (c instanceof JTextComponent)
                     ((JTextComponent)c).setText("");
             }
         });

         add(box);
         add(rem);
     }

     public static void main(String[] args) {
         EventQueue.invokeLater(new Runnable() {
             public void run() {
                 JFrame f = new JFrame("test");
                 f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
                 test t = new test();
                 f.add(t,BorderLayout.CENTER);
                 f.pack();
                 f.setLocationRelativeTo(null);
                 f.setVisible(true);
             }
         });
     }
}

--

Knute Johnson