// Fig. 12.13: ComboBoxTest.java

// Using a JComboBox to select an image to display.

// Java core packages

import java.awt.*;

import java.awt.event.*;

// Java extension packages

import javax.swing.*;

public class ComboBoxTest extends JFrame {

private JComboBox imagesComboBox;

private JLabel label;

private String names[] =

{ "bug1.gif", "bug2.gif", "travelbug.gif", "buganim.gif" };

private Icon icons[] = { new ImageIcon( names[ 0 ] ),

new ImageIcon( names[ 1 ] ), new ImageIcon( names[ 2 ] ),

new ImageIcon( names[ 3 ] ) };

// set up GUI

public ComboBoxTest()

{

super( "Testing JComboBox" );

// get content pane and set its layout

Container container = getContentPane();

container.setLayout( new FlowLayout() );

// set up JComboBox and register its event handler

imagesComboBox = new JComboBox( names );

imagesComboBox.setMaximumRowCount( 3 );

imagesComboBox.addItemListener(

// anonymous inner class to handle JComboBox events

new ItemListener() {

// handle JComboBox event

public void itemStateChanged( ItemEvent event )

{

// determine whether check box selected

if ( event.getStateChange() == ItemEvent.SELECTED )

label.setIcon( icons[

imagesComboBox.getSelectedIndex() ] );

}

} // end anonymous inner class

); // end call to addItemListener

container.add( imagesComboBox );

// set up JLabel to display ImageIcons

label = new JLabel( icons[ 0 ] );

container.add( label );

setSize( 350, 100 );

setVisible( true );

}

// execute application

public static void main( String args[] )

{

ComboBoxTest application = new ComboBoxTest();

application.addWindowListener(new WindowAdapter()

{ public void windowClosing( WindowEvent event )

{

System.exit( 0 );

}

}

);

}

} // end class ComboBoxTest