import java.awt.*;import java.awt.event.*;import javax.swing.*;/* * CustomComboBoxDemo.java is a 1.4 application that uses the following files: *   images/Bird.gif *   images/Cat.gif *   images/Dog.gif *   images/Rabbit.gif *   images/Pig.gif */public class CustomComboBoxDemo extends JPanel {    ImageIcon[] images;    String[] petStrings = {"Bird", "Cat", "Dog", "Rabbit", "Pig"};    /*     * Despite its use of EmptyBorder, this panel makes a fine content     * pane because the empty border just increases the panel's size     * and is "painted" on top of the panel's normal background.  In     * other words, the JPanel fills its entire background if it's     * opaque (which it is by default); adding a border doesn't change     * that.     */    public CustomComboBoxDemo() {        super(new BorderLayout());        //Load the pet images and create an array of indexes.        images = new ImageIcon[petStrings.length];        Integer[] intArray = new Integer[petStrings.length];        for (int i = 0; i < petStrings.length; i++) {            intArray[i] = new Integer(i);            images[i] = createImageIcon("images/" + petStrings[i] + ".gif");            if (images[i] != null) {                images[i].setDescription(petStrings[i]);            }        }        //Create the combo box.        JComboBox petList = new JComboBox(intArray);        ComboBoxRenderer renderer= new ComboBoxRenderer();        renderer.setPreferredSize(new Dimension(200, 130));        petList.setRenderer(renderer);        petList.setMaximumRowCount(3);        //Lay out the demo.        add(petList, BorderLayout.PAGE_START);        setBorder(BorderFactory.createEmptyBorder(20,20,20,20));    }    /** Returns an ImageIcon, or null if the path was invalid. */    protected static ImageIcon createImageIcon(String path) {        java.net.URL imgURL = CustomComboBoxDemo.class.getResource(path);        if (imgURL != null) {            return new ImageIcon(imgURL);        } else {            System.err.println("Couldn't find file: " + path);                return null;        }    }    /**     * Create the GUI and show it.  For thread safety,     * this method should be invoked from the     * event-dispatching thread.     */    private static void createAndShowGUI() {        //Make sure we have nice window decorations.        JFrame.setDefaultLookAndFeelDecorated(true);        //Create and set up the window.        JFrame frame = new JFrame("CustomComboBoxDemo");        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);        //Create and set up the content pane.        JComponent newContentPane = new CustomComboBoxDemo();        newContentPane.setOpaque(true); //content panes must be opaque        frame.setContentPane(newContentPane);        //Display the window.        frame.pack();        frame.setVisible(true);    }    public static void main(String[] args) {        //Schedule a job for the event-dispatching thread:        //creating and showing this application's GUI.        javax.swing.SwingUtilities.invokeLater(new Runnable() {            public void run() {                createAndShowGUI();            }        });    }    class ComboBoxRenderer extends JLabel                           implements ListCellRenderer {        private Font uhOhFont;        public ComboBoxRenderer() {            setOpaque(true);            setHorizontalAlignment(CENTER);            setVerticalAlignment(CENTER);        }        /*         * This method finds the image and text corresponding         * to the selected value and returns the label, set up         * to display the text and image.         */        public Component getListCellRendererComponent(                                           JList list,                                           Object value,                                           int index,                                           boolean isSelected,                                           boolean cellHasFocus) {            //Get the selected index. (The index param isn't            //always valid, so just use the value.)            int selectedIndex = ((Integer)value).intValue();            if (isSelected) {                setBackground(list.getSelectionBackground());                setForeground(list.getSelectionForeground());            } else {                setBackground(list.getBackground());                setForeground(list.getForeground());            }            //Set the icon and text.  If icon was null, say so.            ImageIcon icon = images[selectedIndex];            String pet = petStrings[selectedIndex];            setIcon(icon);            if (icon != null) {                setText(pet);                setFont(list.getFont());            } else {                setUhOhText(pet + " (no image available)",                            list.getFont());            }            return this;        }        //Set the font and text when no image was found.        protected void setUhOhText(String uhOhText, Font normalFont) {            if (uhOhFont == null) { //lazily create this font                uhOhFont = normalFont.deriveFont(Font.ITALIC);            }            setFont(uhOhFont);            setText(uhOhText);        }    }}