Java Swing Loading Animation

问题:

I Would like to realize the following loading animation with java swing :

The circle has to spin clockwise.

What would be the best way to make it ?

Thank you very much.

回答1:

You can use the Animated Icon class to create your own animation using your existing icon.

回答2:

Just use an ImageIcon and an animated gif. see setImageObserver in ImageIcon.

Loading icons can be made using a variety of online generators such as AjaxLoad.

回答3:

Hopefully it's not too late for this.

I managed to get the animated gif inside my JPanel this way:

private JPanel loadingPanel() {
    JPanel panel = new JPanel();
    BoxLayout layoutMgr = new BoxLayout(panel, BoxLayout.PAGE_AXIS);
    panel.setLayout(layoutMgr);

    ClassLoader cldr = this.getClass().getClassLoader();
    java.net.URL imageURL   = cldr.getResource("img/spinner.gif");
    ImageIcon imageIcon = new ImageIcon(imageURL);
    JLabel iconLabel = new JLabel();
    iconLabel.setIcon(imageIcon);
    imageIcon.setImageObserver(iconLabel);

    JLabel label = new JLabel("Loading...");
    panel.add(iconLabel);
    panel.add(label);
    return panel;
}

Some points of this approach:
1. The image file is within the jar;
2. ImageIO.read() returns a BufferedImage, which doesn't update the ImageObserver;
3. Another alternative to find images that are bundled in the jar file is to ask the Java class loader, the code that loaded your program, to get the files. It knows where things are.

So by doing this I was able to get my animated gif inside my JPanel and it worked like a charm.

回答4:

This could be drawn with a custom component or a custom icon, using regular Java2D calls. To me it looks like an Arc2D with a fairly thick BasicStroke drawn with a GradientPaint.

Alternately, export frames from Inkscape (or other graphics program) and load them as images.