Graphical User Interfaces - JavaTech: An Introduction to Scientific and Technical Computing with Java - page 219

Figure 7.6 The JList
component provides a list
of items for the user to
choose. The component
can allow for single or
multiple item selections.
Here, for our ListPanel
class in UITestApplet ,
only one item can be
selected.
Instead of an ActionListener , the JList sends its events to a
ListSelectionListener (which appears in the javax.swing.event
package). This version of our ControlPanel implements the ListSelec-
tionListener interface and provides a valueChanged() method. The
selected item is determined from the list and the OutputPanel 's background is
set to that color.
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.event.*;
/**
* The ListPanel holds the JList component with items
* that determine the color of the output panel.
**/
public class ListPanel extends JPanel
implements ListSelectionListener
{
OutputPanel fOutputPanel;
/** Constructor adds a JList to the panel. **/
ListlPanel (OutputPanel output - panel) {
fOutputPanel = output - panel;
String [] colors ={
" Red " , " Green " , " Blue " , " Yellow " , " White " , " Black "} ;
JList color - list = new JList (colors);
// Show only 4 items in the list at a time.
color - list.setVisibleRowCount (4);