PROBLEM : SetSelectedIndex with MultiColumn JComboBox

Question

Hello,
I've got a problem with my MultiColumn (2 Column) JComboBox.
I had use in my ListCellRenderer a panel wich contains 2 labels (One for the code and another for the description of my item).
Everything work very well, except the "SetSelectedIndex" and "SetSelectedItem", when i do that the label2 appears over the label1...and i obtains some very strang things....
Is there anybody who got the solution or who got the same problem?
Thx for the futur response.
PS: I'm sorry for my bad english and my bad explanations, I'm french...

Answer 1

Here is an example of a combo box with 2 columns using a JPanel implementing ListCellRenderer. Note that there are other ways to get appropriate background and foreground colors, but this is just a quick sample:
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.net.*;
import java.io.*;
import javax.swing.*;
import javax.swing.event.*;
public class Test extends JFrame
     public static void main(String[] args)
          new Test();
     public Test()
          Container c = getContentPane();
          c.setLayout(new BorderLayout());
          c.setBackground(Color.gray);
          Item[] items = {
                    new Item("Item 1", "Value 1"),
                    new Item("Item 2", "Value 2"),
                    new Item("Item 3", "Value 3"),
                    new Item("Item 4", "Value 4")
          JComboBox jcb = new JComboBox(items);
          jcb.setPreferredSize(new Dimension(24, 24));
          jcb.setRenderer(new ItemRenderer());
          c.add(jcb, BorderLayout.NORTH);
          setSize(200, 100);
          setLocationRelativeTo(null);
          setDefaultCloseOperation(EXIT_ON_CLOSE);
          setVisible(true);
     // The items to display in the combobox...
     class Item
          String itemName = "";
          String itemValue = "";
          public Item(String name, String value)
               itemName = name;
               itemValue = value;
     // The combobox's renderer...
     class ItemRenderer extends JPanel implements ListCellRenderer
          private JLabel          nameLabel = new JLabel(" ");
          private JLabel          valueLabel = new JLabel(" ");
          public ItemRenderer()
               setOpaque(true);
               setLayout(new GridLayout(1, 2));
               add(nameLabel);
               add(valueLabel);
          public Component getListCellRendererComponent(
                                   JList list,
                                   Object value,
                                   int index,
                                   boolean isSelected,
                                   boolean cellHasFocus )
               nameLabel.setText( ((Item)value).itemName );
               valueLabel.setText( ((Item)value).itemValue );
               if (isSelected)
                    setBackground(Color.black);
                    nameLabel.setForeground(Color.white);
                    valueLabel.setForeground(Color.white);
               else
                    setBackground(Color.white);
                    nameLabel.setForeground(Color.black);
                    valueLabel.setForeground(Color.black);
               return this;
}I'm not sure, but the key to your problem may be with the opacity of your renderer. Let us know what you come up with. Cheers,
Chris