BaseNavigationController.swift

internal class BaseNavigationController: UINavigationController {

    /// Indicates if a UIViewController is currently being pushed onto this navigation controller
    private var duringPushAnimation = false

    override func viewDidLoad() {
        super.viewDidLoad()
        self.delegate = self // to track when a view controller is being pushed
        self.interactivePopGestureRecognizer?.delegate = self // for swipe the pop gesture recogniser
    }

    override func pushViewController(_ viewController: UIViewController, animated: Bool) {
        duringPushAnimation = true
        super.pushViewController(viewController, animated: animated)
    }
  
    deinit {
        delegate = nil
        interactivePopGestureRecognizer?.delegate = nil
    }
}