原理
在window上加一个UIImageView它的图片和启动图的图片一样，然后再调整动画
运行展示
demo百度云连接:http://pan.baidu.com/s/1c0QcYu0
more：网上看了一个哥们的封装的还不错，分析下代码：
宏定义
#define iphone4x_3_5 ([UIScreen mainScreen].bounds.size.height==480.0f) #define iphone5x_4_0 ([UIScreen mainScreen].bounds.size.height==568.0f) #define iphone6_4_7 ([UIScreen mainScreen].bounds.size.height==667.0f) #define iphone6Plus_5_5 ([UIScreen mainScreen].bounds.size.height==736.0f || [UIScreen mainScreen].bounds.size.height==414.0f)
获取启动图片，你创建的图片资源文件里面的
/**
* 获取启动图片
*/
+(UIImage *)launchImage{ NSString *imageName=@"LaunchImage-700"; if(iphone5x_4_0) imageName=@"LaunchImage-700-568h"; if(iphone6_4_7) imageName = @"LaunchImage-800-667h"; if(iphone6Plus_5_5) imageName = @"LaunchImage-800-Portrait-736h"; UIImage *image = [UIImage imageNamed:imageName]; NSAssert(image != nil, @"Charlin Feng提示您：请添加启动图片！"); return image;
}
设置动画根据需要合一随意变的（这里它就是添加到控制器上面的）
+(void)animWithWindow:(UIWindow *)window image:(UIImage *)image{
UIImageView *imageV = [[UIImageView alloc] initWithFrame:[UIScreen mainScreen].bounds];
imageV.image = image==nil?[self launchImage]:image;
[window.rootViewController.view addSubview:imageV];
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
[UIView animateWithDuration:1.5 animations:^{
[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
imageV.transform=CGAffineTransformMakeScale(1.5, 1.5);
imageV.alpha = ;
} completion:^(BOOL finished) {
[imageV removeFromSuperview];
}];
});
}
调用（ok）
[WJLaunchImage animWithWindow:self.window image:nil];