A Simple Yet Powerful RootNavigation Handler

AppRootChanger.swift

// MARK: - Protocol for Root Changing
protocol RootChanging {
    func changeRoot(to viewController: UIViewController, in navigationController: UINavigationController)
}

// MARK: - Concrete Root Changer
class AppRootChanger: RootChanging {
    
    func changeRoot(to viewController: UIViewController, in navigationController: UINavigationController) {
        let direction: CATransitionSubtype = .fromRight
        let duration = 0.3

        let transition = CATransition()
        transition.type = CATransitionType.push
        transition.subtype = direction
        transition.duration = duration
        transition.timingFunction = CAMediaTimingFunction(name: .easeInEaseOut)

        navigationController.view.layer.add(transition, forKey: kCATransition)
        navigationController.setViewControllers([viewController], animated: false)
    }
}

AppRootNavigationController.swift

// MARK: - AppRootNavigationController
class AppRootNavigationController: UINavigationController {
    private var cancellables = Set<AnyCancellable>()
    var isDarkContent: Bool = true {
        didSet { setNeedsStatusBarAppearanceUpdate() }
    }
    static let changeAppRoot = PassthroughSubject<UIViewController, Never>()

    private let rootChanger: RootChanging

    init(rootChanger: RootChanging = AppRootChanger()) {
        self.rootChanger = rootChanger
        super.init(nibName: nil, bundle: nil)
    }

    required init?(coder aDecoder: NSCoder) {
        self.rootChanger = AppRootChanger()
        super.init(coder: aDecoder)
    }

    override var preferredStatusBarStyle: UIStatusBarStyle {
        isDarkContent ? .darkContent : .lightContent
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        Self.changeAppRoot
            .receive(on: DispatchQueue.main)
            .sink { [weak self] viewController in
                guard let self = self else { return }
                self.rootChanger.changeRoot(to: viewController, in: self)
            }
            .store(in: &cancellables)
    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        setNavigationBarHidden(true, animated: animated)
    }
}