Display value and Actual value in JComboBox

[kashwini Kulkarni]

Hello,

I want to display values from my database in a JComboBox, where the item being displayed must be the name and the value of the item must be the Srno (primary key) .

Is there any way to display two values in JComboBox ( same as SELECT in HTML) where one being displayed and other being just the value.




Thanks in Advance
KAshwini

[Rob Camick]

If I understand the question then try this:

import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import javax.swing.plaf.basic.*;

public class ComboBoxItem extends JFrame implements ActionListener
{
	public ComboBoxItem()
	{
		Vector model = new Vector();
		model.addElement( new Item(1, "car" ) );
		model.addElement( new Item(2, "plane" ) );
		model.addElement( new Item(3, "train" ) );
		model.addElement( new Item(4, "boat" ) );

		JComboBox comboBox;

		//  Easiest approach is to just override toString() method
		//  of the Item class

		comboBox = new JComboBox( model );
		comboBox.setDragEnabled(true);
		comboBox.addActionListener( this );
		getContentPane().add(comboBox, BorderLayout.NORTH );

		//  Most flexible approach is to create a custom render
		//  to diplay the Item data

		comboBox = new JComboBox( model );
		comboBox.setDragEnabled(true);
		comboBox.setRenderer( new ItemRenderer() );
		comboBox.addActionListener( this );
		getContentPane().add(comboBox, BorderLayout.SOUTH );
	}

	public void actionPerformed(ActionEvent e)
	{
		JComboBox comboBox = (JComboBox)e.getSource();
		Item item = (Item)comboBox.getSelectedItem();
		System.out.println( item.getId() + " : " + item.getDescription() );
	}

	class ItemRenderer extends BasicComboBoxRenderer
	{
		public Component getListCellRendererComponent(
			JList list, Object value, int index,
			boolean isSelected, boolean cellHasFocus)
		{
			super.getListCellRendererComponent(list, value, index,
				isSelected, cellHasFocus);

			if (value != null)
			{
				Item item = (Item)value;
				setText( item.getDescription().toUpperCase() );
			}

			if (index == -1)
			{
				Item item = (Item)value;
				setText( "" + item.getId() );
			}


			return this;
		}
	}

	class Item
	{
		private int id;
		private String description;

		public Item(int id, String description)
		{
			this.id = id;
			this.description = description;
		}

		public int getId()
		{
			return id;
		}

		public String getDescription()
		{
			return description;
		}

		public String toString()
		{
			return description;
		}
	}

	public static void main(String[] args)
	{
		JFrame frame = new ComboBoxItem();
		frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
		frame.pack();
		frame.setVisible( true );
	 }

}