Recently, I am working on graphic project. This project I faced is a big challenge to me. Here is a sloution to show the progress bar when loading the image from the net.
PS:
If you install the JAI, it will break the progress interrupt.
See this in Sun's Bug Database http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4842452
1 import java.awt.BorderLayout;
2 import java.awt.event.ActionEvent;
3 import java.awt.event.ActionListener;
4 import java.awt.image.BufferedImage;
5 import java.io.IOException;
6 import java.net.MalformedURLException;
7 import java.net.URL;
8 import java.util.Iterator;
9
10 import javax.imageio.ImageIO;
11 import javax.imageio.ImageReader;
12 import javax.imageio.event.IIOReadProgressListener;
13 import javax.imageio.stream.ImageInputStream;
14 import javax.swing.*;
15
16 public class IIOProgressTest
17 {
18 public static void main(String[] args)
19 {
20 try {
21 UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
22 } catch (Exception e) {
23 e.printStackTrace();
24 }
25
26 final JLabel imageLabel = new JLabel();
27 JScrollPane scrollPane = new JScrollPane(imageLabel);
28 final JButton startBtn = new JButton("Load Image");
29 final JProgressBar progressBar = new JProgressBar();
30 progressBar.setVisible(false);
31 JPanel p = new JPanel(new BorderLayout(5, 5));
32 p.add(startBtn, BorderLayout.WEST);
33 p.add(progressBar, BorderLayout.CENTER);
34
35 final IIOReadProgressListener progressListener = new IIOReadProgressListener() {
36 public void imageStarted(ImageReader source, int imageIndex)
37 {
38 SwingUtilities.invokeLater(new Runnable()
39 {
40 public void run()
41 {
42 startBtn.setEnabled(false);
43 progressBar.setValue(0);
44 progressBar.setVisible(true);
45 invalidate();
46
47 }
48 });
49 }
50 public void imageProgress(ImageReader source, final float percentageDone)
51 {
52 SwingUtilities.invokeLater(new Runnable()
53 {
54 public void run()
55 {
56 System.out.println("percentageDone" + percentageDone);
57 progressBar.setValue((int) (percentageDone));
58 }
59 });
60 }
61 public void imageComplete(ImageReader source)
62 {
63 SwingUtilities.invokeLater(new Runnable()
64 {
65 public void run()
66 {
67 startBtn.setEnabled(true);
68 progressBar.setValue(100);
69 progressBar.setVisible(false);
70 }
71 });
72 }
73
74 public void sequenceStarted(ImageReader source, int minIndex) {}
75 public void sequenceComplete(ImageReader source) {}
76 public void thumbnailStarted(ImageReader source, int imageIndex, int thumbnailIndex) {}
77 public void thumbnailProgress(ImageReader source, float percentageDone) {}
78 public void thumbnailComplete(ImageReader source) {}
79 public void readAborted(ImageReader source) {}
80 };
81
82 startBtn.addActionListener(new ActionListener()
83 {
84 public void actionPerformed(ActionEvent e)
85 {
86 final String urlStr = JOptionPane.showInputDialog(
87 SwingUtilities.getWindowAncestor(startBtn), "Input image URL");
88 if (urlStr == null) {
89 return;
90 }
91
92 new Thread() {
93 public void run()
94 {
95 try {
96 URL url = new URL(urlStr);
97 ImageInputStream iis = ImageIO.createImageInputStream(url.openStream());
98 Iterator iter = ImageIO.getImageReaders(iis);
99 if (iter.hasNext()) {
100 ImageReader reader = (ImageReader) iter.next();
101 reader.setInput(iis);
102 reader.addIIOReadProgressListener(progressListener);
103 BufferedImage image = reader.read(reader.getMinIndex());
104 final ImageIcon icon = new ImageIcon(image);
105
106 SwingUtilities.invokeLater(new Runnable()
107 {
108 public void run()
109 {
110 imageLabel.setIcon(icon);
111 imageLabel.revalidate();
112 }
113 });
114 }
115 } catch (MalformedURLException e) {
116 e.printStackTrace();
117 } catch (IOException e) {
118 e.printStackTrace();
119 }
120 }
121 }.start();
122 }
123 });
124
125 JFrame f = new JFrame("IIOProgressTest");
126 f.getContentPane().setLayout(new BorderLayout(5, 5));
127 f.getContentPane().add(scrollPane, BorderLayout.CENTER);
128 f.getContentPane().add(p, BorderLayout.SOUTH);
129 f.setSize(800, 600);
130 f.setLocationRelativeTo(null);
131 f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
132 f.setVisible(true);
133 }
134 }
135
posted on 2005-08-16 12:19
Pudgy's World 阅读(897)
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