程序启动的时候，实现Default 图片向四周扩散的动画

原理是作为在程序启动的代码里面生成一个UIImageView， 此view的图片就是程序中的Default.png图片。

- (void)applicationDidFinishLaunching:(UIApplication *)application 

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［self showSplashView］；

 

｝

- (void)showSplashView {
    splashView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 20, 320, 460)];
    UIImage *image = [[UIImage alloc] initWithContentsOfFile:[[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"Default.png"]];
    splashView.image = image;
	[image release];
	[window addSubview:splashView];
    [window bringSubviewToFront:splashView];
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:0.3];
    [UIView setAnimationTransition:UIViewAnimationTransitionNone forView:window cache:YES];
    [UIView setAnimationDelegate:self];
    [UIView setAnimationDidStopSelector:@selector(startupAnimationDone:finished:context:)];
    splashView.alpha = 0.0;
    splashView.frame = CGRectMake(-60, -40, 440, 600);
    [UIView commitAnimations];
}

- (void)startupAnimationDone:(NSString *)animationID finished:(NSNumber *)finished context:(void *)context {
    [splashView removeFromSuperview];
    [splashView release];
}





调用的时候：
［self showSplashView］；