How do you hold all the items of a collectionView in place when the device rotates without locking the device in portrait mode?

Question

I would like to build a collectionView that holds all the cells in place when the user rotates the device without locking the device's orientation into portrait mode. I have tried invalidating the layout but to no avail. Thank you for your help.

Answer 1

Based on your comment, that you want to keep all screens in portrait orientation, but know if the device is in landscape orientation without rotating the interface (for a camera screen), you should…

• set Supported interface orientations to portrait in your info.plist

• detect the device orientation using CMMotionManager…

  let motionManager = CMMotionManager()
  var currentOrientation = UIDeviceOrientation.portrait
  
  func montiorOrientation() {
      motionManager.startAccelerometerUpdates(to: OperationQueue()) { data, error in
          if let error = error {
              print("CM orientation error - \(error)")
              return
          }
          let acceleration = data!.acceleration
  
          let orientation: UIDeviceOrientation = fabs(acceleration.y) < fabs(acceleration.x) ?
              (acceleration.x > 0 ? .landscapeRight : .landscapeLeft) :
              (acceleration.y > 0 ? self.currentOrientation : .portrait) // Ignore portraitUpsideDown
  
          if orientation != self.currentOrientation {
              DispatchQueue.main.async {
                  self.currentOrientation = orientation
              }
          }
  
      }
  }