UIViewController transparent background

Question

I am creating a viewcontroller in this way:

 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;

The viewcontroller is not full screen, so you can still see the previous one. I want to be able to see it, but lock it. Just like when you use ios facebook sharing, you see the background, but it becomes darker and you can't interact with it. How can I do this?

score 4 · Accepted Answer · answered Dec 05 '12 at 18:08

I believe the problem is that you’re displaying it using -presentModalViewController:animated:. Using that method carries with it some assumptions about the view controller you’re hosting; one of the assumptions it makes (on iPhone-type devices, at least) is that the view controller takes up the entire screen and is opaque.

To get around this, try adding the modal view controller’s view to the current view controller’s view manually. You’ll need to set the view controller hierarchy up to match the view hierarchy, so your code would look like this:

[self addChildViewController:vc];
[self.view addSubview:vc.view];

You’ll need to adjust the incoming view’s frame to position it within its new superview, but that should allow you more freedom.

I tried the code you provided me but it gives the same result as [self presentModalViewController:vc animated:NO]; — Alessandro, Dec 05 '12 at 19:57
Have you set the `frame` property of the incoming view controller’s `view` property? — Jeff Kelley, Dec 05 '12 at 20:13

score 4 · Answer 2 · edited May 23 '17 at 12:16

4

My workaround is to take a screenshot with code, pass the UIImage as a parameter to the new UIViewController, and display it as a background image. In that way it appears transparent, and the you don't have to disable the underlying controls that might be reachable/accessible.

edited May 23 '17 at 12:16

Community

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answered Dec 04 '13 at 15:06

kjoelbro

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Good idea, you can even blur that screenshot to make it iOS7 like :) – SarpErdag Aug 14 '14 at 12:30
Superb idea but won't this run a bit slowly on older devices? – Supertecnoboff Sep 09 '15 at 13:13

score 2 · Answer 3 · answered Jan 11 '17 at 07:40

iOS8+

You can use below code snippet for iOS8+, its worked for me

SecondViewController *secondViewController = [[SecondViewController alloc] init];
secondViewController.modalPresentationStyle = UIModalPresentationOverCurrentContext;           
[self presentViewController:secondViewController animated:YES completion:nil];

UIViewController transparent background

3 Answers3