Completely move to other view and don't allow to go back in SwiftUI

Question

I\'m developing a simple iOS app with SwiftUI with two views: a LogInView() and a HomeView().

What I want is really simple: when the user c

Answer 1

The answer by @kontiki is probably the most SwiftUI-y, but I will present a different solution, probably not as good! But maybe more flexible/scalable.

You can swap rootView of UIHostingController:

SceneDelegate

class SceneDelegate: UIResponder, UIWindowSceneDelegate {
    var window: UIWindow?
    fileprivate lazy var appCoordinator: AppCoordinator = {

        let rootViewController: UIHostingController = .init(rootView: EmptyView().eraseToAny())

        window?.rootViewController = rootViewController

        let navigationHandler: (AnyScreen, TransitionAnimation) -> Void = { [unowned rootViewController, window] (newRootScreen: AnyScreen, transitionAnimation: TransitionAnimation) in

            UIView.transition(
                with: window!,
                duration: 0.5,
                options: transitionAnimation.asUIKitTransitionAnimation,
                animations: { rootViewController.rootView = newRootScreen },
                completion: nil
            )
        }


        return AppCoordinator(
            dependencies: (
                securePersistence: KeyValueStore(KeychainSwift()),
                preferences: .default
            ),
            navigator: navigationHandler
        )
    }()

    func scene(
        _ scene: UIScene,
        willConnectTo session: UISceneSession,
        options connectionOptions: UIScene.ConnectionOptions
    ) {
        self.window = .fromScene(scene)
        appCoordinator.start()
    }
}

enum TransitionAnimation {
    case flipFromLeft
    case flipFromRight
}

private extension TransitionAnimation {
    var asUIKitTransitionAnimation: UIView.AnimationOptions {
        switch self {
        case .flipFromLeft: return UIView.AnimationOptions.transitionFlipFromLeft
        case .flipFromRight: return UIView.AnimationOptions.transitionFlipFromRight
        }
    }
}

AppCoordinator

And here is the AppCoordinator:

    final class AppCoordinator {

    private let preferences: Preferences
    private let securePersistence: SecurePersistence
    private let navigationHandler: (AnyScreen, TransitionAnimation) -> Void

    init(

        dependencies: (securePersistence: SecurePersistence, preferences: Preferences),

        navigator navigationHandler: @escaping (AnyScreen, TransitionAnimation) -> Void

    ) {

        self.preferences = dependencies.preferences
        self.securePersistence = dependencies.securePersistence
        self.navigationHandler = navigationHandler
    }
}

// MARK: Internal
internal extension AppCoordinator {

    func start() {
        navigate(to: initialDestination)
    }
}

// MARK: Destination
private extension AppCoordinator {
    enum Destination {
        case welcome, getStarted, main
    }

    func navigate(to destination: Destination, transitionAnimation: TransitionAnimation = .flipFromLeft) {

        let screen = screenForDestination(destination)
        navigationHandler(screen, transitionAnimation)
    }

    func screenForDestination(_ destination: Destination) -> AnyScreen {
        switch destination {
        case .welcome: return AnyScreen(welcome)
        case .getStarted: return AnyScreen(getStarted)
        case .main: return AnyScreen(main)
        }
    }

    var initialDestination: Destination {
        guard preferences.hasAgreedToTermsAndPolicy else {
            return .welcome
        }

        guard securePersistence.isAccountSetup else {
            return .getStarted
        }

        return .main
    }

}

// MARK: - Screens
private extension AppCoordinator {

    var welcome: some Screen {
        WelcomeScreen()
            .environmentObject(
                WelcomeViewModel(
                    preferences: preferences,
                    termsHaveBeenAccepted: { [unowned self] in self.start() }
                )
            )
    }

    var getStarted: some Screen {
        GetStartedScreen()
            .environmentObject(
                GetStartedViewModel(
                    preferences: preferences,
                    securePersistence: securePersistence,
                    walletCreated: { [unowned self] in self.navigate(to: .main) }
                )
        )
    }

    var main: some Screen {
        return MainScreen().environmentObject(
            MainViewModel(
                preferences: preferences,
                securePersistence: securePersistence,
                walletDeleted: { [unowned self] in
                    self.navigate(to: .getStarted, transitionAnimation: .flipFromRight)
                }
            )
        )
    }
}