Swift - Snapshotting a view that has not been rendered results in an empty snapshot

Question

My var:

@IBOutlet weak var imageView: UIImageView!

Take photo function:

func takePhoto(){
        let picker = UIImagePickerController()

        picker.delegate = self
        picker.sourceType = .Camera

        presentViewController(picker, animated: true, completion: nil)
    }

Error message:

Snapshotting a view that has not been rendered results in an empty snapshot. Ensure your view has been rendered at least once before snapshotting or snapshot after screen updates

Any ideas?

When do you call take a photo? i.e. view did load or view did appear? — Mitchell Currie, Aug 12 '15 at 01:13
And where are you actually taking a snapshot? I do not see the code to snapshot the view. — Mitchell Currie, Aug 12 '15 at 01:19
A snapshot is rendering a UIView to an image. Are you using any presentation controller or transition/animation frameworks? show us the code for presentViewController — Mitchell Currie, Aug 12 '15 at 01:23
@MitchellCurrie - There is no other code, that is all code i used. All i used was this: http://www.ioscreator.com/tutorials/take-photo-tutorial-ios8-swift — Eri-Sklii, Aug 12 '15 at 01:29
What exactly happens, does the picker come up at all? or does it start to transition. I would suspect you are not on the main thread except your IBAction should be triggered there, is this correct? — Mitchell Currie, Aug 12 '15 at 01:39
Well, everything works actually, but the error just keeps coming. — Eri-Sklii, Aug 12 '15 at 01:42
http://stackoverflow.com/questions/18890003/uiimagepickercontroller-error-snapshotting-a-view-that-has-not-been-rendered-re — Mitchell Currie, Aug 12 '15 at 01:49
@MitchellCurrie - Anything for swift? I have never used Obj-C. — Eri-Sklii, Aug 12 '15 at 01:54
It's probably nothing to worry about at this stage of your learning, but if you wish to dive deeper, try changing the order of page appearances or presenting it in a different modal style. I repeat, just double check this is all happening from main thread (thread 0) — Mitchell Currie, Aug 12 '15 at 02:10
My advice, ignore it and move on - come back once you understand more. It will make sense. — Mitchell Currie, Aug 12 '15 at 02:18

Jeremy · Answer 1 · 2016-08-13T07:37:23.727

2

I have had the same problem - I have two options once I have called the VC - From Photos or Selfie - and when I select Selfie i.e. camera Xcode prints that message but not ion I select Photos - so my guess is its a bug in the camera app. It has never crashed my app so I ignore it Code:

@IBAction func openCameraButton(sender: AnyObject) {
    if UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.Camera) == true {
        camera = true
        imagePicker.delegate = self
        imagePicker.sourceType = .Camera
        imagePicker.allowsEditing = false
        self.presentViewController(imagePicker, animated: true, completion: nil)
    }else{
        noCamera()

    }
}

edited Aug 13 '16 at 07:37

answered Aug 12 '16 at 16:43

Jeremy

145
1
2
13

I don't get it, could you explain more while giving feedback on the OP please ? – Gar Aug 12 '16 at 17:03
I segue to a VC which has an Image view and a toolbar with 2 options one to get a photo from a library and the other to use the camera. The only time I get the warning when I select the camera and the camera app has loaded: – Jeremy Aug 13 '16 at 06:59

score 1 · Answer 2 · answered May 04 '16 at 22:51

1

Make sure you have:

super.viewDidLoad()

in your viewDidLoad func.

answered May 04 '16 at 22:51

FlatDog

2,685
2
16
19

score 1 · Answer 3 · answered Sep 02 '16 at 15:36

put your self.presentViewController or your self.navigationController?.showViewController inside dispatch_async(dispatch_get_main_queue()) {

dispatch_async(dispatch_get_main_queue()) {
  self.presentViewController(imagePicker, animated: true, completion: nil)
}

score 0 · Answer 4 · answered Aug 12 '15 at 02:14

0

Your code looks fine. I would restart XCode and double check your didFinishPickingImage method to make sure it's closing properly. The issue could be with your transitions. This has happened to me several times in the past and never became a big deal.

answered Aug 12 '15 at 02:14

This is my "didFinishPackingImage" method: http://pastebin.com/Zyrpu0sL - Do you see anything wrong here? – Eri-Sklii Aug 12 '15 at 20:41
Looks fine to me. Are you getting an error with it? Or is the issue the original question? – Aug 12 '15 at 20:42
I get that warning error from the original question. – Eri-Sklii Aug 12 '15 at 21:12
Have you checked the camera permissions in device settings? – Aug 12 '15 at 21:41
If your camera can be accessed to take a photo. – Aug 12 '15 at 21:48
As i said; everything works, but still that errors comes. – Eri-Sklii Aug 12 '15 at 21:55
I would just ignore for now...doesn't seem to be a real issue. – Aug 12 '15 at 21:56

score 0 · Answer 5 · answered May 18 '16 at 09:17

0

You are probably assigning it to another UIImageView too fast, try to save it in another variable first and in the func ViewDidLoad put that image into the UIImageView. That worked for me!

answered May 18 '16 at 09:17

Cano

13
5

score 0 · Answer 6 · answered Jul 16 '16 at 07:36

0

goto setting -> privacy -> camera and enable or disable camera access for individual apps

This issue seems to occur when the key: "CFBundleDisplayName" has an empty string value in the Info.plist.

answered Jul 16 '16 at 07:36

shan

136
7

Swift - Snapshotting a view that has not been rendered results in an empty snapshot

6 Answers6

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