UIStoryboard *sb = [UIStoryboard storyboardWithName:@"PhotoViewControlleriPhone" bundle:nil];
                                UIViewController *vc = [sb instantiateInitialViewController];

                               vc.view.backgroundColor = [UIColor clearColor];
                               self.modalPresentationStyle = UIModalPresentationCurrentContext;

                               [self presentModalViewController:vc animated:NO];

                               vc.view.frame = CGRectMake(imageView.frame.origin.x,imageView.frame.origin.y + 64,imageView.frame.size.width,200.000000);

                               vc.view.layer.cornerRadius = 10; // this value vary as per your desire
                               vc.view.clipsToBounds = YES;

viewcontroller不是全屏,因此您仍然可以看到前一个.我想能够看到它,但锁定它.就像当你使用ios facebook分享时,你会看到背景,但它会变得更暗,你无法与之交互.我怎样才能做到这一点？