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I have been doing some experiments with a custom camera using AVFoundation and so far everything's been great. The AVCam example got me very far and I am quite happy with the results.

However, one thing I still don't get is how the iOS default Camera app handles rotations. It seems like the background does not rotate at all but all the overlay controls do.

This is probably not a camera-specific question but how could I achieve this behaviour?

TLDR: Have a background camera layer, controls on top, how to rotate controls without rotating the background layer?

defer
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    You could override `willAnimateRotationToInterfaceOrientation:duration:` and manually resize all the controls. It may take a bit of tweaking to achieve the desired effect, but it has always worked for me. http://developer.apple.com/library/ios/#documentation/uikit/reference/UIViewController_Class/Reference/Reference.html – Greg Dec 30 '12 at 00:19
  • Alternatively, you could take the hackish approach and insert the camera view into the root `UIWindow` of the app, and set the background of the view controller with the controls to transparent, so that the view controller rotates but the window doesn't, and the camera view in the window is visible behind it. – Greg Dec 30 '12 at 00:21
  • Your first suggestion was my initial thought, I will probably go with it. The second one won' work on iOS6 and upwards because child views rotation capabilities must be a proper subset of the parents rotation capabilities. – defer Jan 04 '13 at 11:30

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I've been wondering on the same...

My guess would be that the native Camera viewController doesn't rotate using the UIViewController rotation mechanism

  • no status bar rotation
  • no 'basic' rotation of subviews - toolbar doesn't move, buttons are animated
  • and of course the view containing the camera preview doesn't rotate :)

Rather it must call [UIDevice beginGeneratingDeviceOrientationNotifications] and handle specific UI update (grey buttons fading position switching, and toolbar buttons image rotation) 

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(yourUpdateMethodForRotation:) notificationName: UIDeviceOrientationDidChangeNotification];
Vinzzz
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