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iOS

Posted by Demetrius Albuquerque
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Demetrius Albuquerque
Python Web Development Techdegree Student 5,071 Points

UIImagePickerController Warning: Attempt to present on UITabBarController while a presentation is in progress!

Im doing the "Build a Self-Destructing Message iPhone App" using XCode 5, iOS 7 and iPhone 5. But when I try to use the imagepickerview, it's does not work well. I see this message on console: Warning: Attempt to present <UIImagePickerController> on <UITabBarController> while a presentation is in progress!

I tried some changes but nothing worked until now, I using that to show the UIImagePickerView

[self presentViewController:self.imagePicker animated:NO completion:nil];

Dismissing on delegate with:

[self dismissViewControllerAnimated:NO completion:nil];

I also tried another codes like:

[self.tabBarController presentViewController:self.imagePicker animated:NO completion:nil];

and

[picker dismissViewControllerAnimated:NO completion:nil];

But I always receive same message.

4 Answers

Keith Klingen
Keith Klingen
9,031 Points
Keith Klingen
Keith Klingen
9,031 Points

This warning appears because of this line in CameraViewController viewWillAppear: [self presentViewController:self.imagePicker animated:NO completion:nil];

Apparently presenting a second view from the first view's viewWillAppear will cause two views to overlap presentations, at least briefly.

I solved this by moving the code to viewDidAppear. Then the problem was it kept re-appearing too often, so you'll have to surround this code with a conditional like so: -(void)viewDidAppear:(BOOL)animated{ [super viewDidAppear:animated]; if(doImagePicker){ doImagePicker = false; [self presentViewController:self.imagePicker animated:NO completion:nil]; } }

BOOL doImagePicker = false; should be set in the .h

doImagePicker = true; will need to be set in imagePickerControllerDidCancel and didFinishPickingMediaWithInfo

Basically, telling the ImagePicker only to run the first time viewDidAppear is called, or after you've previously cancelled the action or chosen an image.

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

its just a warning. the app still works correctly right?

Jack Solomon
Jack Solomon
839 Points
Jack Solomon
Jack Solomon
839 Points

I've had that issue heaps of times, but it is never going to really be a problem. If you still want to get rid of it, it's essentially because for a very short period of time there are no views, or two views presented. To fix this, present the view, or dismiss, using completion. i.e:

[self dismissViewControllerAnimated:NO completion:^{ //Code to show view here [self presentViewController:self.imagePicker animated:NO completion:nil]; }];

You might need to modify this a bit (I haven't looked into it properly to fit the self destruct message app).

Fabrizio Rinaldi
Fabrizio Rinaldi
5,359 Points
Fabrizio Rinaldi
Fabrizio Rinaldi
5,359 Points

I can't see messages received inside the app, and i didn't change anything inside.

I got the same problem too!