Я пытаюсь добавить возможность запуска веб-URL в базовую демонстрацию галереи Java Swing ImageIcon для SUN (Oracle):
http://docs.oracle.com/javase/tutorial/uiswing/components/icon.html#example
Требование
Цель состоит в том, чтобы создать средство запуска веб-ссылок Swing GUI, которое может запускать ссылку через веб-браузер пользователя по умолчанию с помощью средства запуска JRE 1.6+ Desktop API, и открывать другой URL-адрес в зависимости от того, какое изображение было нажато в последний раз.
Проблема
Кажется, у меня проблема в том, что каждый раз, когда в конструкторе ThumbnailAction создается новый ImageIcon, кажется, что он не разрушает предыдущее изображение и просто рисует поверх него. Нежелательным побочным эффектом является то, что MouseListeners и метаданные старого изображения все еще активны, поэтому попытка щелкнуть, чтобы запустить URL-адрес, фактически загружает URL-адрес ранее загруженных изображений, а также URL-адрес текущего изображения в фокусе. Если вы посмотрите журналы печати консоли, вы также можете увидеть запуск MouseEntered и Exited несколько раз, по одному разу для каждого изображения, которое было заменено. Поэтому, если пользователь совершит 3 или 4 обмена, он запустит столько URL-адресов. Не желаемый эффект.
Если кто-нибудь знает, в чем проблема, это будет оценено, вот мои модификации файла " IconDemoApp.java " (ОБНОВЛЕНО 2012-01-31):
/*
* 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.
*/
package components;
import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Desktop;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeSet;
import javax.swing.AbstractAction;
import javax.swing.BorderFactory;
import javax.swing.Box;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JToolBar;
import javax.swing.SwingUtilities;
import javax.swing.SwingWorker;
/**
* This application is intended to demonstrate the loading of image files into icons
* for use in a Swing user interface. It creates a toolbar with a thumbnail preview
* of each image. Clicking on the thumbnail will show the full image
* in the main display area.
*
* IconDemoApp.java requires the following files: <br>
* The following files are copyright 2006 spriggs.net and licensed under a
* Creative Commons License (http://creativecommons.org/licenses/by-sa/3.0/)
* <br>
* images/sunw01.jpg <br>
* images/sunw02.jpg <br>
* images/sunw03.jpg <br>
* images/sunw04.jpg <br>
* images/sunw05.jpg <br>
*
* @author Collin Fagan
* @date 7/25/2007
* @version 2.0
*/
public class IconDemoApp extends JFrame {
/**
* Main entry point to the demo. Loads the Swing elements on the "Event
* Dispatch Thread".
*
* @param args
*/
public static void main(String args[]) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
IconDemoApp app = new IconDemoApp();
app.setVisible(true);
}
});
}
/*
* MissingIcon
* Internal class for how to recover from missing icons.
* (displays empty image placeholder with red X and white background)
*/
class MissingIcon implements Icon {
private int width = 32;
private int height = 32;
private BasicStroke stroke = new BasicStroke(4);
public void paintIcon(Component c, Graphics g, int x, int y) {
Graphics2D g2d = (Graphics2D) g.create();
g2d.setColor(Color.WHITE);
g2d.fillRect(x +1 ,y + 1,width -2 ,height -2);
g2d.setColor(Color.BLACK);
g2d.drawRect(x +1 ,y + 1,width -2 ,height -2);
g2d.setColor(Color.RED);
g2d.setStroke(stroke);
g2d.drawLine(x +10, y + 10, x + width -10, y + height -10);
g2d.drawLine(x +10, y + height -10, x + width -10, y + 10);
g2d.dispose();
}
public int getIconWidth() {
return width;
}
public int getIconHeight() {
return height;
}
}
/**
* Default constructor for the demo.
*/
public IconDemoApp() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setTitle("Icon Demo: Please Select an Image");
// A label for displaying the pictures
photographLabel.setVerticalTextPosition(JLabel.BOTTOM);
photographLabel.setHorizontalTextPosition(JLabel.CENTER);
photographLabel.setHorizontalAlignment(JLabel.CENTER);
photographLabel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
// We add two glue components. Later in process() we will add thumbnail buttons
// to the toolbar inbetween thease glue compoents. This will center the
// buttons in the toolbar.
buttonBar.add(Box.createGlue());
buttonBar.add(Box.createGlue());
add(buttonBar, BorderLayout.SOUTH);
add(photographLabel, BorderLayout.CENTER);
setSize(400, 300);
// this centers the frame on the screen
setLocationRelativeTo(null);
// start the image loading SwingWorker in a background thread
loadimages.execute();
}
/**
* SwingWorker class that loads the images a background thread and calls publish
* when a new one is ready to be displayed.
*
* We use Void as the first SwingWroker param as we do not need to return
* anything from doInBackground().
*/
private SwingWorker<Void, ThumbnailAction> loadimages = new SwingWorker<Void, ThumbnailAction>() {
/**
* Creates full size and thumbnail versions of the target image files.
*/
@Override
protected Void doInBackground() throws Exception {
for (int i = 0; i < titles.length; i++) {
ImageIcon icon;
icon = createImageIcon(imagedir + thumbs[i], titles[i]);
ThumbnailAction thumbAction;
if(icon != null){
ImageIcon thumbnailIcon = new ImageIcon(getScaledImage(icon.getImage(), 32, 32));
thumbAction = new ThumbnailAction(icon, thumbnailIcon, titles[i], descs[i], links[i]);
}else{
// the image failed to load for some reason
// so load a placeholder instead
thumbAction = new ThumbnailAction(placeholderIcon, placeholderIcon, titles[i], descs[i], links[i]);
}
publish(thumbAction);
}
// unfortunately we must return something, and only null is valid to
// return when the return type is void.
return null;
}
/**
* Process all loaded images.
*/
@Override
protected void process(List<ThumbnailAction> chunks) {
for (ThumbnailAction thumbAction : chunks) {
JButton thumbButton = new JButton(thumbAction);
// add the new button BEFORE the last glue
// this centers the buttons in the toolbar
buttonBar.add(thumbButton, buttonBar.getComponentCount() - 1);
}
}
};
/**
* Creates an ImageIcon if the path is valid.
* @param String - resource path
* @param String - description of the file
*/
protected ImageIcon createImageIcon(String path, String description) {
java.net.URL imgURL = getClass().getResource(path);
if (imgURL != null) {
return new ImageIcon(imgURL, description);
}
else {
System.err.println("Couldn't find file: " + path);
return null;
}
}
/**
* Resizes an image using a Graphics2D object backed by a BufferedImage.
* @param srcImg - source image to scale
* @param w - desired width
* @param h - desired height
* @return - the new resized image
*/
private Image getScaledImage(Image srcImg, int w, int h) {
BufferedImage resizedImg = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = resizedImg.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
g2.drawImage(srcImg, 0, 0, w, h, null);
g2.dispose();
return resizedImg;
}
/**
* Action class that shows the image specified in it's constructor.
*/
private class ThumbnailAction extends AbstractAction implements MouseListener {
private Icon displayPhoto; // The icon if the full image we want to display.
/**
* @param Icon - The full size photo to show in the button.
* @param Icon - The thumbnail to show in the button.
* @param String - The descriptioon of the icon.
*/
public ThumbnailAction(Icon photo, Icon thumb, String title, String desc, String link) {
displayPhoto = photo;
// The short description becomes the title of the window.
putValue(SHORT_DESCRIPTION, title);
// The long description becomes the tooltip of a button.
putValue(LONG_DESCRIPTION, desc);
// The DEFAULT action on click is to launch this URL
putValue(DEFAULT, link);
// The LARGE_ICON_KEY is the key for setting the icon when an Action is applied to a button.
putValue(LARGE_ICON_KEY, thumb);
}
/**
* Shows the full image in the main area and sets the application title.
*/
public void actionPerformed(ActionEvent e) {
photographLabel.setIcon(displayPhoto);
setTitle("Icon Demo - " + getValue(SHORT_DESCRIPTION).toString());
photographLabel.setToolTipText("<html>" + getValue(LONG_DESCRIPTION) + "</html>");
photographLabel.validate();
photographLabel.updateUI();
photographLabel.repaint();
photographLabel.addMouseListener(this);
}
/**
* Listen for clicks to send user to a URL or launch an application
* @param e
*/
@Override
public void mouseClicked(MouseEvent e) {
int clicked = e.getClickCount();
if (clicked > 0) {
/*************************************/
/* Code for launching Browser BEGIN */
Desktop desktop = null;
if (Desktop.isDesktopSupported()) {
desktop = Desktop.getDesktop();
}
URI uri = null;
try {
uri = new URI((String)this.getValue(DEFAULT)); //pass the URL from ImageIcon to Browser
if (desktop.isSupported(Desktop.Action.BROWSE)) {
desktop.browse(uri); //url passed
}
else {
System.out.println("Unable to open default browser to: "+uri);
}
}
catch(IOException ioe) {
ioe.printStackTrace();
}
catch(URISyntaxException use) {
use.printStackTrace();
}
/* Code for launching Browser END */
/*************************************/
}
else {
System.out.println("Clicked: " + clicked);
}
}
@Override
public void mousePressed(MouseEvent e) {
System.out.println("Mouse pressed (# of clicks: " + e.getClickCount() + ") " + e);
}
@Override
public void mouseReleased(MouseEvent e) {
System.out.println("Mouse released (# of clicks: " + e.getClickCount() + ") " + e);
}
@Override
public void mouseEntered(MouseEvent e) {
System.out.println("Mouse entered: " + e);
}
@Override
public void mouseExited(MouseEvent e) {
System.out.println("Mouse exited: " + e);
}
}
private JLabel photographLabel = new JLabel();
private JToolBar buttonBar = new JToolBar();
private String imagedir = "images/";
private MissingIcon placeholderIcon = new MissingIcon();
// List of all the image files to load.
private String[] thumbs = { "sunw01.jpg", "sunw02.jpg", "sunw03.jpg", "sunw04.jpg", "sunw05.jpg"};
// List of all the descriptions of the image files. These correspond one to one with the image file names
private String[] titles = { "SunLogo", "Clocktower", "ClocktowerWest", "Mansion", "SunAuditorium" };
// List of all descriptions (descs) to use as tooltips.
private String[] descs = { "The Original SUNW Logo", "The Clocktower frontal view", "The Clocktower from the West", "The Mansion on the hill!", "The infamouse Sun campus auditorium"};
// List of all links to send a user to on click action.
private String[] links = { "http://example.com/#1", "http://example.com/#2", "http://example.com/#3", "http://example.com/#4", "http://example.com/#5"};
}