Mega Code Archive
Fading button
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import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
/*
* FadingButton_2008.java
*
* Created on May 2, 2007, 4:11 PM
*
* Copyright (c) 2007, Sun Microsystems, Inc
* 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 the TimingFramework project nor 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.
*/
/**
*
* @author Chet
*/
public class FadingButton_2008 extends JButton implements ActionListener {
float alpha = 1.0f; // current opacity of button
Timer timer; // for later start/stop actions
int animationDuration = 2000; // each animation will take 2 seconds
long animationStartTime; // start time for each animation
BufferedImage buttonImage = null;
/** Creates a new instance of FadingButton_2008 */
public FadingButton_2008(String label) {
super(label);
setOpaque(false);
timer = new Timer(30, this);
addActionListener(this);
}
public void paint(Graphics g) {
// Create an image for the button graphics if necessary
if (buttonImage == null || buttonImage.getWidth() != getWidth()
|| buttonImage.getHeight() != getHeight()) {
buttonImage = getGraphicsConfiguration().createCompatibleImage(getWidth(), getHeight());
}
Graphics gButton = buttonImage.getGraphics();
gButton.setClip(g.getClip());
// Have the superclass render the button for us
super.paint(gButton);
// Make the graphics object sent to this paint() method translucent
Graphics2D g2d = (Graphics2D) g;
AlphaComposite newComposite = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, alpha);
g2d.setComposite(newComposite);
// Copy the button's image to the destination graphics, translucently
g2d.drawImage(buttonImage, 0, 0, null);
}
/**
* This method receives both click events (which start and stop the animation)
* and Timer events (which animate the alpha of the button).
*/
public void actionPerformed(ActionEvent ae) {
if (ae.getSource().equals(this)) {
// button click
if (!timer.isRunning()) {
animationStartTime = System.nanoTime() / 1000000;
this.setText("Stop Animation");
timer.start();
} else {
timer.stop();
this.setText("Start Animation");
// reset alpha to opaque
alpha = 1.0f;
}
} else {
// timer event
// calculate the elapsed fraction
long currentTime = System.nanoTime() / 1000000;
long totalTime = currentTime - animationStartTime;
if (totalTime > animationDuration) {
animationStartTime = currentTime;
}
float fraction = (float) totalTime / animationDuration;
fraction = Math.min(1.0f, fraction);
// This calculation will cause alpha to go from 1 to 0 and back to 1
// as the fraction goes from 0 to 1
alpha = Math.abs(1 - (2 * fraction));
// redisplay our button with its new alpha value
repaint();
}
}
private static void createAndShowGUI() {
JFrame f = new JFrame("Fading Button");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(300, 300);
JPanel checkerboard = new Checkerboard();
checkerboard.add(new FadingButton_2008("Start Animation"));
f.add(checkerboard);
f.setVisible(true);
}
public static void main(String args[]) {
Runnable doCreateAndShowGUI = new Runnable() {
public void run() {
createAndShowGUI();
}
};
SwingUtilities.invokeLater(doCreateAndShowGUI);
}
/**
* Displays checkerboard background
*/
private static class Checkerboard extends JPanel {
private static final int DIVISIONS = 10;
static final int CHECKER_SIZE = 60;
public void paintComponent(Graphics g) {
g.setColor(Color.white);
g.fillRect(0, 0, getWidth(), getHeight());
g.setColor(Color.BLACK);
for (int stripeX = 0; stripeX < getWidth(); stripeX += CHECKER_SIZE) {
for (int y = 0, row = 0; y < getHeight(); y += CHECKER_SIZE / 2, ++row) {
int x = (row % 2 == 0) ? stripeX : (stripeX + CHECKER_SIZE / 2);
g.fillRect(x, y, CHECKER_SIZE / 2, CHECKER_SIZE / 2);
}
}
}
}
}
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