让LaunchImage停留一段时间再消失

方法一 ####使用LaunchImage加载启动图片

- (void) setUpLauchIvWithLaunchImage {
    UIWindow *keyWindow = [[[UIApplication sharedApplication] delegate] window];
    CGSize viewSize = keyWindow.bounds.size;
    NSString *viewOrientation = @"Portrait";    //横屏请设置成 @"Landscape"
    NSString *launchImage = nil;
    
    NSArray* imagesDict = [[[NSBundle mainBundle] infoDictionary] valueForKey:@"UILaunchImages"];
    for (NSDictionary* dict in imagesDict)
    {
        CGSize imageSize = CGSizeFromString(dict[@"UILaunchImageSize"]);
        
        if (CGSizeEqualToSize(imageSize, viewSize) && [viewOrientation isEqualToString:dict[@"UILaunchImageOrientation"]])
        {
            launchImage = dict[@"UILaunchImageName"];
        }
    }
    
    UIImageView *launchView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:launchImage]];
    launchView.frame = self.view.bounds;
    launchView.contentMode = UIViewContentModeScaleAspectFill;
    [self.view addSubview:launchView];
    
    [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];
                         
                     }];
}

使用LaunchScreen.storyboard加载启动图片

- (void) setUpLauchIvWithLaunchScreen {

    UIImage *launchImage = [UIImage imageNamed:@"ElementStartUpPg"];
    UIImageView *launchView = [[UIImageView alloc] initWithImage:launchImage];
    
    launchView.frame = self.view.bounds;
    launchView.contentMode = UIViewContentModeScaleAspectFill;
    [self.view addSubview:launchView];
    
    [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];
                         
                     }];
}