Swing 闪屏加载和延迟技巧
1 引言
我们经常在启动一些程序的时候，会出现一个屏保的闪屏，这个闪屏是一副关于该程序的Logo图片，比如eclipse等等，有的时候并且伴有一些启动信息；
2 limeWire的闪屏
闪屏的实现代码如下：
SplashScreen splashScreen = SplashScreen.getSplashScreen();
Frame splash = null;
Image splashImage = null; // begin with null, assuming we can get it from SplashScreen
// show initial splash screen only if there are no arguments
if (args == null || args.length == 0) {
Rectangle bounds;
// If the splash screen existed & was visible,
// then we want to take the image of the splash screen
// and the bounds it was displayed at, so that
// when we convert to an AWT image, the same image
// is shown at the same place.
if(splashScreen != null && splashScreen.isVisible()) {
bounds = splashScreen.getBounds();
splashImage = Toolkit.getDefaultToolkit().createImage(splashScreen.getImageURL());
}
闪屏的显示和关闭：
if(splashImage != null) {
splash = AWTSplashWindow.splash(splashImage, bounds);
} else if (splashScreen != null && splashScreen.isVisible()) {
// If we couldn't find an image to show via AWT, then just close
// the existing splash and be done with it.
splashScreen.close();
}
获取图片：
private static Image getSplashImage() {
URL imageURL = ClassLoader.getSystemResource("org/limewire/ui/swing/mainframe/resources/splash.png");
if (imageURL != null) {
return Toolkit.getDefaultToolkit().createImage(imageURL);
} else {
return null;
}
}
3 给“他”展示的时间
闪屏启动以后，我们必须给出这个闪屏一直在前段，以便我们后端能够加载程序；
在limeWire中，故意的采用了反射来加载程序，以便能够故意的延迟时间给闪屏：
Class<?> loadClass = Class.forName("org.limewire.ui.swing.GuiLoader");
Object loadInstance = loadClass.newInstance();
Method loadMethod = loadClass.getMethod("load", new Class[] { String[].class, Frame.class, Image.class } );
loadMethod.invoke(loadInstance, args, splash, splashImage);
在程序加载成功需要显示下一个GUI界面的时候，会有新的线程来关闭该闪屏；
显示新的对话框；
SwingUtils.invokeNowOrWait(new Runnable() {
@Override
public void run() {
if (awtSplash != null) {
awtSplash.setVisible(false);
}
//must warn users about sharing documents again after an upgrade
SharingSettings.WARN_SHARING_DOCUMENTS_WITH_WORLD.setValue(true);
boolean confirmed =
new IntentDialog(LimeWireUtils.getLimeWireVersion(),
virusEngine.get()).confirmLegal();
if (!confirmed) {
System.exit(0);
}
if (awtSplash != null) {
awtSplash.setVisible(true);
}
}
});