效果如图：

2016-05-13 13_52_11.gif

由于项目需要在启动图后加载广告，所以把动画加载了广告页面。

实现方法

1.在appdelegate的didFinshLaunchingWithOptions方法里面实现如下代码：
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
self.window.backgroundColor = [UIColor whiteColor];
//这里设置window的根视图控制器
areaVc = [[XSTAreaProvinceViewController alloc] init];
    UINavigationController * nav = [[UINavigationController alloc] initWithRootViewController:areaVc];
    nav.navigationBar.barTintColor = SET_COLOR(@"3FC1FF");
    nav.navigationBar.translucent = NO;
    areaVc.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
    [nav.navigationBar setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor whiteColor]}];
    self.window.rootViewController = nav;
[self.window makeKeyAndVisible]；
//这里将启动图取出
[self setLaunchImage];

//设置状态栏为白色
[[UIApplication sharedApplication] setStatusBarStyle:UIStatusBarStyleLightContent];

return YES;

}
1.启动后再一次从info.plist的字典里面获取到LunachImages（启动图的数组），接着把图片取出来加在window上，接着写个动画效果就行，因为你已经设置好window的根视图控制器，这里启动图加载的时间为默认
具体实现代码：
- (void)setLaunchImage{
CGSize viewSize =self.window.bounds.size;//获取当前屏幕Size
NSStringviewOrientation =@"Portrait";//横屏请设置成 @"Landscape"
NSStringlaunchImage =nil;

//从info.plist文件中获取启动图的数组，这里会返回一个数组（里满是你设置好的启动图）
NSArray* imagesDict = [[[NSBundle mainBundle] infoDictionary] valueForKey:@"UILaunchImages"];
for(NSDictionary* dict in imagesDict) {
    CGSize imageSize =CGSizeFromString(dict[@"UILaunchImageSize"]);
    这里取出数组里面和当前屏幕尺寸相同的iamge
    if(CGSizeEqualToSize(imageSize, viewSize) && [viewOrientation isEqualToString:dict[@"UILaunchImageOrientation"]]) {

        launchImage = dict[@"UILaunchImageName"];
    }
}

UIImageView * launchView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:launchImage]];

launchView.frame=self.window.bounds;
launchView.contentMode=UIViewContentModeScaleAspectFill;
[self.window addSubview:launchView];
//动画效果(你也可以这只其他，这种timeOut效果不错，用过MBProgressHUD人都知道)
 //在两秒内将alpha设置为0，之后在移除
[UIView animateWithDuration:2.0f delay:0.0f options:UIViewAnimationOptionBeginFromCurrentState
                animations:^{
                    launchView.alpha=0.0f;
                    launchView.layer.transform=CATransform3DScale(CATransform3DIdentity,1.2,1.2,1);
                }
                completion:^(BOOL finished) {
                    [launchView removeFromSuperview];
            }];
}