CheckBoxDemo.java

/*
 * Copyright (c) 1995, 2008, Oracle and/or its affiliates. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Oracle or the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package javademo.swing.button.CheckBoxDemo;

import java.awt.BorderLayout;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.event.KeyEvent;

import javax.swing.BorderFactory;
import javax.swing.ImageIcon;
import javax.swing.JCheckBox;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

/*
 * CheckBoxDemo.java requires 16 image files in the images/geek
 * directory: 
 * geek-----.gif, geek-c---.gif, geek--g--.gif, geek---h-.gif, geek----t.gif,
 * geek-cg--.gif, ..., geek-cght.gif.
 */
@SuppressWarnings("serial")
public class CheckBoxDemo extends JPanel implements ItemListener
{
    JCheckBox chinButton;
    
    JCheckBox glassesButton;
    
    JCheckBox hairButton;
    
    JCheckBox teethButton;
    
    /*
     * Four accessory choices provide for 16 different
     * combinations. The image for each combination is
     * contained in a separate image file whose name indicates
     * the accessories. The filenames are "geek-XXXX.gif"
     * where XXXX can be one of the following 16 choices.
     * The "choices" StringBuffer contains the string that
     * indicates the current selection and is used to generate
     * the file name of the image to display.

       ----             //zero accessories

       c---             //one accessory
       -g--
       --h-
       ---t

       cg--             //two accessories
       c-h-
       c--t
       -gh-
       -g-t
       --ht

       -ght             //three accessories
       c-ht
       cg-t
       cgh-

       cght             //all accessories
     */

    StringBuffer choices;
    
    JLabel pictureLabel;
    
    public CheckBoxDemo()
    {
        super(new BorderLayout());
        
        // Create the check boxes.
        chinButton = new JCheckBox("Chin");
        chinButton.setMnemonic(KeyEvent.VK_C);
        chinButton.setSelected(true);
        
        glassesButton = new JCheckBox("Glasses");
        glassesButton.setMnemonic(KeyEvent.VK_G);
        glassesButton.setSelected(true);
        
        hairButton = new JCheckBox("Hair");
        hairButton.setMnemonic(KeyEvent.VK_H);
        hairButton.setSelected(true);
        
        teethButton = new JCheckBox("Teeth");
        teethButton.setMnemonic(KeyEvent.VK_T);
        teethButton.setSelected(true);
        
        // Register a listener for the check boxes.
        chinButton.addItemListener(this);
        glassesButton.addItemListener(this);
        hairButton.addItemListener(this);
        teethButton.addItemListener(this);
        
        // Indicates what's on the geek.
        choices = new StringBuffer("cght");
        
        // Set up the picture label
        pictureLabel = new JLabel();
        pictureLabel.setFont(pictureLabel.getFont().deriveFont(Font.ITALIC));
        updatePicture();
        
        // Put the check boxes in a column in a panel
        JPanel checkPanel = new JPanel(new GridLayout(0, 1));
        checkPanel.add(chinButton);
        checkPanel.add(glassesButton);
        checkPanel.add(hairButton);
        checkPanel.add(teethButton);
        
        add(checkPanel, BorderLayout.LINE_START);
        add(pictureLabel, BorderLayout.CENTER);
        setBorder(BorderFactory.createEmptyBorder(20, 20, 20, 20));
    }
    
    /** Listens to the check boxes. */
    public void itemStateChanged(ItemEvent e)
    {
        int index = 0;
        char c = '-';
        Object source = e.getItemSelectable();
        
        if (source == chinButton)
        {
            index = 0;
            c = 'c';
        }
        else if (source == glassesButton)
        {
            index = 1;
            c = 'g';
        }
        else if (source == hairButton)
        {
            index = 2;
            c = 'h';
        }
        else if (source == teethButton)
        {
            index = 3;
            c = 't';
        }
        
        // Now that we know which button was pushed, find out
        // whether it was selected or deselected.
        if (e.getStateChange() == ItemEvent.DESELECTED)
        {
            c = '-';
        }
        
        // Apply the change to the string.
        choices.setCharAt(index, c);
        
        updatePicture();
    }
    
    protected void updatePicture()
    {
        // Get the icon corresponding to the image.
        ImageIcon icon = createImageIcon("images/geek/geek-" + choices.toString() + ".gif");
        pictureLabel.setIcon(icon);
        pictureLabel.setToolTipText(choices.toString());
        if (icon == null)
        {
            pictureLabel.setText("Missing Image");
        }
        else
        {
            pictureLabel.setText(null);
        }
    }
    
    /** Returns an ImageIcon, or null if the path was invalid. */
    protected static ImageIcon createImageIcon(String path)
    {
        java.net.URL imgURL = CheckBoxDemo.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()
    {
        // Create and set up the window.
        JFrame frame = new JFrame("CheckBoxDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        
        // Create and set up the content pane.
        JComponent newContentPane = new CheckBoxDemo();
        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();
            }
        });
    }
}