Force landscape mode in one ViewController using Swift

Question

I am trying to force only one view in my application on landscape mode, I am calling

override func shouldAutorotate() -> Bool {
    print(\"shouldAutoro         


        

Answer 1

I faced a similar issue in my project. It only has support for portrait. The ViewController structure is that, Navigation contained a controller (I called A), and a long Scrollview in A controller. I need A(portrait) present to B(landscape right).

In the beginning I tried the method below and it seemed to work but eventually I found a bug in it.

Swift 5 & iOS12

// In B controller just override three properties

override var shouldAutorotate: Bool {
    return false
}

override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
    return UIInterfaceOrientationMask.landscapeRight
}

override var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation {
    return .landscapeRight
}

And then something become strange. When controller B dismiss to controller A. The ScrollView in controller A has been slid some point.

So I used another method, so I rotate the screen when viewWillAppear. You can see the code for that below.

// In controller B
// not need override shouldAutorotate , supportedInterfaceOrientations , preferredInterfaceOrientationForPresentation

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    let appDel = UIApplication.shared.delegate as! AppDelegate
    appDel.currentOrientation = .landscapeRight
    UIDevice.current.setValue( UIInterfaceOrientation.landscapeRight.rawValue, forKey: "orientation")
    UIViewController.attemptRotationToDeviceOrientation()
}

//in viewWillDisappear rotate to portrait can not fix the bug


override func dismiss(animated flag: Bool, completion: (() -> Void)? = nil) {
    let appDel = UIApplication.shared.delegate as! AppDelegate
    appDel.currentOrientation = .portrait
    UIDevice.current.setValue( UIInterfaceOrientation.portrait.rawValue, forKey: "orientation")
    UIViewController.attemptRotationToDeviceOrientation() //must call 
    super.dismiss(animated: true, completion: nil)
}

// in AppDelegate
// the info plist is only supported portrait also, No need to change it

var currentOrientation : UIInterfaceOrientationMask = .portrait


func application(_ application: UIApplication, supportedInterfaceOrientationsFor window: UIWindow?) -> UIInterfaceOrientationMask {
    return self.currentOrientation
}