implement Icon interface and add icon to JButton

Description

Demo Code

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.awt.*;
import javax.swing.*;

/* This class is used by CustomIconDemo.java. */
class ArrowIcon implements Icon, SwingConstants {
    private int width = 9;
    private int height = 18;

    private int[] xPoints = new int[4];
    private int[] yPoints = new int[4];

    public ArrowIcon(int direction) {
        if (direction == LEADING) {
            xPoints[0] = width;//from w  ww.j a  va  2s  .  c  o m
            yPoints[0] = -1;
            xPoints[1] = width;
            yPoints[1] = height;
            xPoints[2] = 0;
            yPoints[2] = height / 2;
            xPoints[3] = 0;
            yPoints[3] = height / 2 - 1;
        } else /* direction == TRAILING */{
            xPoints[0] = 0;
            yPoints[0] = -1;
            xPoints[1] = 0;
            yPoints[1] = height;
            xPoints[2] = width;
            yPoints[2] = height / 2;
            xPoints[3] = width;
            yPoints[3] = height / 2 - 1;
        }
    }

    public int getIconHeight() {
        return height;
    }

    public int getIconWidth() {
        return width;
    }

    public void paintIcon(Component c, Graphics g, int x, int y) {
        if (c.isEnabled()) {
            g.setColor(c.getForeground());
        } else {
            g.setColor(Color.gray);
        }

        g.translate(x, y);
        g.fillPolygon(xPoints, yPoints, xPoints.length);
        g.translate(-x, -y); //Restore graphics object
    }
}
/* 
 * CustomIconDemo.java (based on ButtonDemo.java) requires the following files:
 *    ArrowIcon.java
 *    images/middle.gif
 */
public class CustomIconDemo extends JPanel implements ActionListener {
    protected JButton b1, b2, b3;

    public CustomIconDemo() {
        Icon leftButtonIcon = new ArrowIcon(SwingConstants.RIGHT);
        Icon middleButtonIcon = createImageIcon("images/middle.gif",
                "the middle button");
        Icon rightButtonIcon = new ArrowIcon(SwingConstants.LEFT);

        b1 = new JButton("Disable middle button", leftButtonIcon);
        b1.setVerticalTextPosition(AbstractButton.CENTER);
        b1.setHorizontalTextPosition(AbstractButton.LEADING);
        b1.setMnemonic(KeyEvent.VK_D);
        b1.setActionCommand("disable");

        b2 = new JButton("Middle button", middleButtonIcon);
        b2.setVerticalTextPosition(AbstractButton.BOTTOM);
        b2.setHorizontalTextPosition(AbstractButton.CENTER);
        b2.setMnemonic(KeyEvent.VK_M);

        b3 = new JButton("Enable middle button", rightButtonIcon);
        //Use the default text position of CENTER, TRAILING (RIGHT).
        b3.setMnemonic(KeyEvent.VK_E);
        b3.setActionCommand("enable");
        b3.setEnabled(false);

        //Listen for actions on buttons 1 and 3.
        b1.addActionListener(this);
        b3.addActionListener(this);

        b1.setToolTipText("Click this button to disable the middle button.");
        b2.setToolTipText("This middle button does nothing when you click it.");
        b3.setToolTipText("Click this button to enable the middle button.");

        //Add Components to this container, using the default FlowLayout. 
        add(b1);
        add(b2);
        add(b3);
    }

    public void actionPerformed(ActionEvent e) {
        if ("disable".equals(e.getActionCommand())) {
            b2.setEnabled(false);
            b1.setEnabled(false);
            b3.setEnabled(true);
        } else {
            b2.setEnabled(true);
            b1.setEnabled(true);
            b3.setEnabled(false);
        }
    }

    /** Returns an ImageIcon, or null if the path was invalid. */
    protected static ImageIcon createImageIcon(String path,
            String description) {
        java.net.URL imgURL = CustomIconDemo.class.getResource(path);
        if (imgURL != null) {
            return new ImageIcon(imgURL, description);
        } 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("CustomIconDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Set up the content pane.
        JComponent newContentPane = new CustomIconDemo();
        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();
            }
        });
    }
}

/*
 * 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
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
implement Icon interface and add icon to JButton - Java Swing

Description

Demo Code

Related Tutorials
