Does the existing modal view manager on top of the Quick Look PreviewController display a checkerboard?

Question

Situation: my application needs to present a full-screen mode when it becomes active (from the background) in order to ask the user for a PIN code. Everything is good. If: if the user views the file using the QLPreviewController , leaves the application and returns, the PIN input controller will be presented modally with the QLPreviewController to which I am QLPreviewController . The PIN code entry is displayed, but when it is rejected, I see a checkerboard-like background that even scrolls. There seems to be some residual PreviewController, but the actual preview data is no longer displayed. Any idea what might trigger this?

Do I need to somehow reload the contents of the preview?

Answer 1

I had a similar problem and managed to fix the problem using the viewWillDisappear or viewDidDisappear . My solution was to subclass QLPreviewController and overwrite these methods with an empty implementation, i.e. Skipping a call to super . I do not know if it is very safe, although I did not encounter problems, and he solved my problem.