问题
I have a simple Swing Java application that performs searches, and the results are shown in a new tab. While the search is running, I want to show a progress icon or animation in the title of the tab. I tried adding a gif icon, but it doesn't animate. Is there a reason why this isn't working?
回答1:
The Swing tutorial about progress bars (and showing progress in general) is a very good place to start. It shows you how to perform long-lasting operations on a worker thread by using a SwingWorker, and updating your UI at certain intervals to show progress of the long-lasting operation to the user. There is another tutorial available for more information on the SwingWorker and concurrency in Swing
And as always, this site is filled with examples. For example a previous answer of mine uses the SwingWorker class to show progress to a user
Edit
As I missed the title of tab part of your question. You could create a 'progress icon' and set that on the tab. The SwingWorker can then be used to update the icon.
An example of such an icon is
, which is basically an image you rotate each time some progress is made. The tabbed pane tutorial shows you how to add icons to your tabs (or even use custom components)
Edit2
As it seems my Mac in combination with JDK1.7 makes it much easier to show an animated gif then on other systems, I created a small SSCCE as well, quite similar to that of Andrew but with a rotating icon which does not look like it has been created by, and I quote, 'demented Chimpanzee'. The rotating icon code comes from this site (I used a stripped down version and added the timer). Only thing I am not too happy about is the fact I need to pass my tabbed pane to the rotating icon to trigger. Possible solution is to pull the timer outside the RotatingIcon class, but hey, it's only an SSCCE . Images are not included but were found with Google.
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTabbedPane;
import javax.swing.Timer;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.AffineTransform;
public class ProgressTabbedPane {
public static void main( String[] args ) {
EventQueue.invokeLater( new Runnable() {
@Override
public void run() {
JFrame frame = new JFrame( "RotatingIcon" );
JTabbedPane tabbedPane = new JTabbedPane( );
tabbedPane.addTab( "Searching", new RotatingIcon( new ImageIcon( "resources/images/progress-indeterminate.png" ), tabbedPane ),
new JLabel( new ImageIcon( "resources/images/rotatingIcon.gif" ) ) );
frame.getContentPane().add( tabbedPane );
frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
frame.pack();
frame.setVisible( true );
}
} );
}
private static class RotatingIcon implements Icon{
private final Icon delegateIcon;
private double angleInDegrees = 90;
private final Timer rotatingTimer;
private RotatingIcon( Icon icon, final JComponent component ) {
delegateIcon = icon;
rotatingTimer = new Timer( 100, new ActionListener() {
@Override
public void actionPerformed( ActionEvent e ) {
angleInDegrees = angleInDegrees + 10;
if ( angleInDegrees == 360 ){
angleInDegrees = 0;
}
component.repaint();
}
} );
rotatingTimer.setRepeats( false );
rotatingTimer.start();
}
@Override
public void paintIcon( Component c, Graphics g, int x, int y ) {
rotatingTimer.stop();
Graphics2D g2 = (Graphics2D )g.create();
int cWidth = delegateIcon.getIconWidth() / 2;
int cHeight = delegateIcon.getIconHeight() / 2;
Rectangle r = new Rectangle(x, y, delegateIcon.getIconWidth(), delegateIcon.getIconHeight());
g2.setClip(r);
AffineTransform original = g2.getTransform();
AffineTransform at = new AffineTransform();
at.concatenate(original);
at.rotate(Math.toRadians( angleInDegrees ), x + cWidth, y + cHeight);
g2.setTransform(at);
delegateIcon.paintIcon(c, g2, x, y);
g2.setTransform(original);
rotatingTimer.start();
}
@Override
public int getIconWidth() {
return delegateIcon.getIconWidth();
}
@Override
public int getIconHeight() {
return delegateIcon.getIconHeight();
}
}
}
A screenshot for reference. A shame the icons do not rotate in the screenshot.
回答2:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
public class ImageOnTab {
ImageOnTab() {
final BufferedImage image = new BufferedImage(
32,32,BufferedImage.TYPE_INT_RGB);
final JTabbedPane pane = new JTabbedPane();
ImageIcon icon = new ImageIcon(image);
pane.addTab( "Progress", icon, new JTree() );
ActionListener listener = new ActionListener() {
int x = 0;
int step = 1;
public void actionPerformed(ActionEvent ae) {
Graphics g = image.createGraphics();
x+=step;
if (step>0) {
if (x>32) {
step=-step;
}
} else if (x<0) {
step=-step;
}
g.setColor(Color.ORANGE);
g.fillRect(0,0,32,32);
g.setColor(Color.RED);
g.fillRect(0,0,x,32);
g.dispose();
pane.repaint();
}
};
Timer timer = new Timer(100,listener);
timer.start();
JOptionPane.showMessageDialog(null, pane);
}
public static void main(String[] args) throws Exception {
//Create the GUI on the event dispatching thread
SwingUtilities.invokeLater(new Runnable(){
@Override
public void run() {
new ImageOnTab();
}
});
}
}
回答3:
@Andrew Thompson
It would be great if the J2SE supported animated GIFs 'out of the box'
in more situations. I tried that animated GIF (nice image, BTW) as a
tab icon, and no, it remains static.
I don't want to read whole ...., but put together code by yours and @trashgod's majesty
1) use Htlm (I'm not good in plain Html)
2) use GlassPane with JLabel#(setOpaque(true))
3) use JLayer (JXLayer is better, becasue Sn'Oracle remove important methods == my view)
4) you have to force ..... for Swing JComponents by @aterai
5) Rob's Animated Icon a few times metioned support by Rob for JTabbedPane
code
import java.awt.*;
import java.awt.event.*;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Random;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.*;
//https://stackoverflow.com/questions/3483485/java-jprogressbar-or-equivalent-in-a-jtabbedpane-tab-title/3484251#3484251
public class JTabbedTest {
private JFrame f = new JFrame();
private JTabbedPane jtp = new JTabbedPane();
private URL url = null;
public JTabbedTest() {
try {
url = new URL("http://pscode.org/media/starzoom-thumb.gif");
} catch (MalformedURLException ex) {
Logger.getLogger(JTabbedTest.class.getName()).log(Level.SEVERE, null, ex);
}
ImageIcon ii = new ImageIcon(url);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jtp.setPreferredSize(new Dimension(400, 200));
createTab("Reds", Color.RED);
createTab("Greens", Color.GREEN);
createTab("Blues", Color.BLUE);
f.add(jtp, BorderLayout.CENTER);
jtp.setTitleAt(2, "<html><img src=" + ii + " width=20 height=20></img></html>");
// change foreground Color for disabled tab
/*jtp.setTitleAt(2, "<html><font color=" + (jtp.isEnabledAt(2) ? "black" : "red") + ">"
+ jtp.getTitleAt(2) + "</font></html>");*/
Rectangle tabBounds = jtp.getBoundsAt(0);
Container glassPane = (Container) f.getRootPane().getGlassPane();
glassPane.setVisible(true);
glassPane.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.weightx = 1.0;
gbc.weighty = 1.0;
gbc.fill = GridBagConstraints.NONE;
gbc.insets = new Insets(tabBounds.y + 23, 0, 0, 5);
gbc.anchor = GridBagConstraints.NORTHEAST;
JButton button = new JButton("My Button Position", ii);
button.setPreferredSize(new Dimension(button.getPreferredSize().width, (int) tabBounds.getHeight() - 2));
glassPane.add(button, gbc);
f.pack();
f.setVisible(true);
}
private void createTab(String name, Color color) {
ProgressIcon icon = new ProgressIcon(color);
jtp.addTab(name, icon, new ColorPanel(jtp, icon));
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
JTabbedTest jTabbedTest = new JTabbedTest();
}
});
}
private static class ColorPanel extends JPanel implements ActionListener {
private static final Random rnd = new Random();
private static final long serialVersionUID = 1L;
private final Timer timer = new Timer(1000, this);
private final JLabel label = new JLabel("Stackoverflow!");
private final JTabbedPane parent;
private final ProgressIcon icon;
private final int mask;
private int count;
public ColorPanel(JTabbedPane parent, ProgressIcon icon) {
super(true);
this.parent = parent;
this.icon = icon;
this.mask = icon.color.getRGB();
this.setBackground(icon.color);
label.setForeground(icon.color);
this.add(label);
timer.start();
}
@Override
public void actionPerformed(ActionEvent e) {
this.setBackground(new Color(rnd.nextInt() & mask));
this.icon.update(count += rnd.nextInt(8));
this.parent.repaint();
}
}
private static class ProgressIcon implements Icon {
private static final int H = 16;
private static final int W = 3 * H;
private Color color;
private int w;
public ProgressIcon(Color color) {
this.color = color;
}
public void update(int i) {
w = i % W;
}
@Override
public void paintIcon(Component c, Graphics g, int x, int y) {
g.setColor(color);
g.fillRect(x, y, w, H);
}
@Override
public int getIconWidth() {
return W;
}
@Override
public int getIconHeight() {
return H;
}
}
}
来源：https://stackoverflow.com/questions/10055336/jtabbedpane-show-task-progress-in-a-tab