CheckBoxSample.java Source code

Introduction

Here is the source code for CheckBoxSample.java

Source

/*
Definitive Guide to Swing for Java 2, Second Edition
By John Zukowski       
ISBN: 1-893115-78-X
Publisher: APress
*/

import java.awt.Color;
import java.awt.Component;
import java.awt.Graphics;
import java.awt.Polygon;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.event.KeyEvent;

import javax.swing.AbstractButton;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JCheckBoxMenuItem;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.UIManager;

public class CheckBoxSample {
    static Icon boyIcon = new ImageIcon("boy-r.jpg");

    static Icon girlIcon = new ImageIcon("girl-r.jpg");

    public static void main(String args[]) {

        ActionListener aListener = new ActionListener() {
            public void actionPerformed(ActionEvent event) {
                AbstractButton aButton = (AbstractButton) event.getSource();
                boolean selected = aButton.getModel().isSelected();
                String newLabel;
                Icon newIcon;
                if (selected) {
                    newLabel = "Girl";
                    newIcon = girlIcon;
                } else {
                    newLabel = "Boy";
                    newIcon = boyIcon;
                }
                aButton.setText(newLabel);
                aButton.setIcon(newIcon);
            }
        };

        ItemListener iListener = new ItemListener() {
            public void itemStateChanged(ItemEvent event) {
                AbstractButton aButton = (AbstractButton) event.getSource();
                int state = event.getStateChange();
                String newLabel;
                Icon newIcon;
                if (state == ItemEvent.SELECTED) {
                    newLabel = "Girl";
                    newIcon = girlIcon;
                } else {
                    newLabel = "Boy";
                    newIcon = boyIcon;
                }
                aButton.setText(newLabel);
                aButton.setIcon(newIcon);
            }
        };

        JFrame frame = new JFrame("CheckBox Example");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JMenuBar bar = new JMenuBar();
        JMenu menu = new JMenu("Menu");
        menu.setMnemonic(KeyEvent.VK_M);
        JCheckBoxMenuItem one = new JCheckBoxMenuItem();
        menu.add(one);
        JCheckBoxMenuItem two = new JCheckBoxMenuItem("Boy");
        menu.add(two);
        JCheckBoxMenuItem three = new JCheckBoxMenuItem(boyIcon);
        menu.add(three);
        JCheckBoxMenuItem four = new JCheckBoxMenuItem("Girl", true);
        menu.add(four);
        JCheckBoxMenuItem five = new JCheckBoxMenuItem("Boy", boyIcon);
        five.addItemListener(iListener);
        menu.add(five);
        Icon stateIcon = new DiamondAbstractButtonStateIcon(Color.black);

        UIManager.put("CheckBoxMenuItem.checkIcon", stateIcon);
        JCheckBoxMenuItem six = new JCheckBoxMenuItem("Girl", girlIcon, true);
        six.addActionListener(aListener);
        menu.add(six);

        bar.add(menu);
        frame.setJMenuBar(bar);
        frame.setSize(350, 250);
        frame.setVisible(true);
    }
}

class DiamondAbstractButtonStateIcon implements Icon {
    private final int width = 10;

    private final int height = 10;

    private Color color;

    private Polygon polygon;

    public DiamondAbstractButtonStateIcon(Color color) {
        this.color = color;
        initPolygon();
    }

    private void initPolygon() {
        polygon = new Polygon();
        int halfWidth = width / 2;
        int halfHeight = height / 2;
        polygon.addPoint(0, halfHeight);
        polygon.addPoint(halfWidth, 0);
        polygon.addPoint(width, halfHeight);
        polygon.addPoint(halfWidth, height);
    }

    public int getIconHeight() {
        return width;
    }

    public int getIconWidth() {
        return height;
    }

    public void paintIcon(Component component, Graphics g, int x, int y) {
        boolean selected = false;
        g.setColor(color);
        g.translate(x, y);
        if (component instanceof AbstractButton) {
            AbstractButton abstractButton = (AbstractButton) component;
            selected = abstractButton.isSelected();
        }
        if (selected) {
            g.fillPolygon(polygon);
        } else {
            g.drawPolygon(polygon);
        }
        g.translate(-x, -y);
    }
}