Custom JComboBox -- MouseListener

Question

Hi. I'm in the process of making a custom JComboBox (called TitledComboBox).
It's going to use a ComboBox as the component that is always visible, but when you click it instead of the standard dropdown, I'm creating a JPopupMenu to replace that. That way I want to avoid the first element (or the selected one) being repeated inside the list.
So I've created my class extending JComboBox, and implemented MouseListener, but I'm unable to make the listener work for the JComboBox layout manager. It works perfectly for the spots on the JComboBox where the LayoutManager doesnt paint (or whatever it does), so the "arrow" doesn't effect the MouseListener....
How can I extend the default JComboBox LayoutManager to have the same MouseListener??

Answer 1

package gui;
import java.awt.Color;
import java.awt.Component;
import java.awt.Graphics;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.*;
@SuppressWarnings("serial")
public class TitledComboBox extends JComboBox implements MouseListener
    @SuppressWarnings("serial")
    private class PopItem extends JMenuItem
         public PopItem(String text)
            setLayout(null);
            setText(text);
            setOpaque(false);
            setBackground(Color.BLACK);
        public void paint(Graphics g)
            super.paint(g);
    @SuppressWarnings("serial")
    private class PopMenu extends JPopupMenu
          public PopMenu()
               this.setLayout(null);
               this.setPopupSize(120, 23*this.getComponentCount());
               this.setOpaque(false);
          public PopMenu(String[] items)
               this();
               for(int i = 0; i < items.length; i++)
                    this.add(new PopItem(items));
               updateSize();
          private void updateSize()
               this.setPopupSize(120, 23*this.getComponentCount());
          public void show(Component arg0, int arg1, int arg2)
               super.show(arg0, arg1, arg2);
               this.setVisible(true);
          public void paint(Graphics g)
               super.paint(g);
     public PopMenu dropdown;
     private TitledComboBox()
          super();
          this.addMouseListener(this);
          this.setVisible(true);
this.setEnabled(false);
     public TitledComboBox(String title)
          this();
          this.addItem(title);
          dropdown = new PopMenu();
     public TitledComboBox(String title, String[] items)
          this();
          this.addItem(title);
          dropdown = new PopMenu(items);
     public void addPopItem(String item)
          dropdown.add(new PopItem(item));
          dropdown.updateSize();
     public void removePopItem(int itemIndex)
          dropdown.remove(itemIndex);
          dropdown.updateSize();
     public void paint(Graphics g)
          this.setEnabled(true);
          super.paint(g);
          this.setEnabled(false);
     public void mouseClicked(MouseEvent m)
dropdown.show(this, 0, 20);
     public void mouseEntered(MouseEvent arg0)
     public void mouseExited(MouseEvent arg0)
     public void mousePressed(MouseEvent arg0)
     public void mouseReleased(MouseEvent arg0)
Using this now gives something very similar to a JComboBox, just without the top element showing. However, I STILL don't know how to get the LayoutManager to be a part of the MouseListener... Please help!
Edited by: Ondkloss on Nov 21, 2007 7:12 AM