如果snapshotViewAfterScreenUpdates失效, 用这个方法替代, 不过要自己创建ImageView 替代方式:

- (UIImage *)imageFromView:(UIView *)snapView {    UIGraphicsBeginImageContext(snapView.frame.size);    CGContextRef context = UIGraphicsGetCurrentContext();    [snapView.layer renderInContext:context];    UIImage *targetImage = UIGraphicsGetImageFromCurrentImageContext();    UIGraphicsEndImageContext();    return targetImage;}

 

UIImage *image = [self imageFromView:fromVC.fromVCImageView];    UIImageView *snapView = [[UIImageView alloc] initWithImage:image];    snapView.frame = fromVC.fromVCImageView.frame;    [containerView addSubview:snapView];