UIDevice.current.setValue(value, forKey: "orientation") does not work if phone held in landscape and tilted 45 - 90 degrees

Question

I'm using

let value = UIInterfaceOrientation.landscapeRight.rawValue
UIDevice.current.setValue(value, forKey: "orientation")

to force the presenting view controller to show in landscape right. This is part of a navigation controller flow. This works as expected, but if the phone is held in landscape and titled between 45 and 90 degrees the view will present in portrait. The method is called and the expected value is correct, but no change to landscape occurs. This can be reproduced in a bare bones project with a navigation controller.

Does anyone have any idea what might cause this behavior?

Answer 1

You could override

func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?)

as described in https://developer.apple.com/reference/uikit/uitraitenvironment/1623516-traitcollectiondidchange

as in

- (void) traitCollectionDidChange: (UITraitCollection *) previousTraitCollection {
    [super traitCollectionDidChange: previousTraitCollection];
    if ((self.traitCollection.verticalSizeClass != previousTraitCollection.verticalSizeClass)
        || (self.traitCollection.horizontalSizeClass != previousTraitCollection.horizontalSizeClass)) {
        // your custom implementation here
    }
}

to maintain your orientation as desired. Alternatively, in XCode, click on your target, choose the General tab, and choose only one allowed orientation.

Answer 2

Try this:

open override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
    get {
        return UIInterfaceOrientationMask.landscapeRight
    }
}

open override var shouldAutorotate: Bool {
    get {
        return false
    }
}

open override var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation {
    get {
        return UIInterfaceOrientation.landscapeRight
    }
}

From @Dragos answer on Setting device orientation in Swift iOS