Autorotation bug in iOS 13

Question

iOS 13/13.1 autorotation seems to be behave differently than iOS 12. For instance, my app allows user to lock interface orientation to portrait or landscape mode in settings.

1. If I have portrait rotation lock on device and return .landscape in supportedInterfaceOrientations, the interface remains in portrait mode until I disable portrait lock orientation on device. This does not seem to be the case with iOS 12. Infact, supportedInterfaceOrientations is not even called in iOS 13!

2. UIViewController.attemptRotationToDeviceOrientation() also does not work in such cases.

The root of the problem is I temporarily return shouldAutorotate to false while the app is initializing and when everything is initialized, I call UIViewController.attemptRotationToDeviceOrientation() to trigger autorotation. It triggers autorotation in iOS 12 but in iOS 13.1 it doesn't works.

Looks like a bug in iOS 13.1 probably. What do I do to force trigger autorotation?

EDIT: Looks like iOS 12.4.1 also ignores UIViewController.attemptRotationToDeviceOrientation(). There is something broken in autorotation in iOS 12.4.1 & above.

To be clear, this is what I want:

a. Even if portrait lock is set on iPhone, I wish my interface to autorotate to landscape mode if required,

b. UIViewController.attemptRotationToDeviceOrientation() alternative that triggers autorotation in all circumstances.

Shirring

supportedInterfaceOrientations will not be called if viewcontroller is presented. It will be called when presented fullscreen, but by default, the UIModalpresentationStyle from iOS 13 is not fullscreen. – Cranmer

Answer 1

From iOS 12.4.1, View Controller should be set to Full Screen to respect the auto-rotate orientation.

let vc = UIViewController()
vc.modalPresentationStyle = .fullScreen
self.present(vc, animated: true, completion: nil)

Godman

Where does modal presentation comes into picture I wonder, the controller is not presented modally. – Shirring

Well.. then set your navigation controller to full screen and return a different supported interface rotation when calling attempt device rotation on view did load. – Godman

This solved it for me. I'm also calling present but because of the presented ViewController having a different preferredInterfaceOrientationForPresentation it is presented like it's a modal by default, maybe it's some iOS 13 behavior? In any case, thanks, this was very simple to add. – Surname

Answer 2

Try this and see if this is something you are looking for:

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.

    }

    @IBAction func btnLandscapeClicked(_ sender: Any) {
        let value = UIInterfaceOrientation.landscapeLeft.rawValue
        UIDevice.current.setValue(value, forKey: "orientation")
    }

    @IBAction func btnPortraitClicked(_ sender: Any) {
        let value = UIInterfaceOrientation.portrait.rawValue
        UIDevice.current.setValue(value, forKey: "orientation")
    }

}

extension UINavigationController {

    override open var shouldAutorotate: Bool {
        get {
            if let visibleVC = visibleViewController {
                return visibleVC.shouldAutorotate
            }
            return super.shouldAutorotate
        }
    }

    override open var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation{
        get {
            if let visibleVC = visibleViewController {
                return visibleVC.preferredInterfaceOrientationForPresentation
            }
            return super.preferredInterfaceOrientationForPresentation
        }
    }

    override open var supportedInterfaceOrientations: UIInterfaceOrientationMask{
        get {
            if let visibleVC = visibleViewController {
                return visibleVC.supportedInterfaceOrientations
            }
            return super.supportedInterfaceOrientations
        }
    }}

Obelia

Well, isn't this a hack or undocumented API? – Shirring

And I do not have any navigation controller in place – Shirring

@DeepakSharma These are all available APIs by iOS SDK. I recommend you to put your ViewControllers in a NavigationController even if you are not using it, to get the same behaviour across your screens. – Obelia

Answer 3

Replying for other people facing this issue, this is what worked for me. Go to the project settings General > Deployment Info and make sure you have checked "Requires full screen" setting.

Then paste the following code after the viewDidLoad block:

// Forbid autorotate
override open var shouldAutorotate: Bool {
   return false
}

// Specify the orientation
override open var supportedInterfaceOrientations: UIInterfaceOrientationMask {
    return .landscape
}

Schutt