如何在 SwiftUI 中使用 UINavigationController

Question

I am trying to create Coordinator to navigate from Screen1 to Screen2

Here is the example of UIKit

class Coordinator: AbstractCoordinator {

    var navigationController: UINavigationController?

    func goToHomeScreen() {
        navigationController?.pushViewController(HomeViewController(coordinator: self), animated: true)
    }

    func start() -> UIViewController {
        self.navigationController = UINavigationController(rootViewController: LoginViewController(coordinator: self))

        return navigationController!
    }
}

This Coordinator is very useful when we are using modular programming. I want to do the same thing in SwiftUI

I know we have to use NavigationView, NavigationLink but I can't understand how should I do in Coordinator

Can someone tell me how can I do it?

Answer 1

For using Coordinator in SwiftUI you need to use two components:

1. Coordinator View and
2. Coordinator Object

The coordinator view is part of the view hierarchy and controls the transition logic and the overall view context of its child views. The coordinator view requires a coordinator object to create view models and allow communication between different scenes. Similar to coordinators in UIKit, we can have a reference to the coordinator from view models of child scenes and trigger transition events in the coordinator based on the business logic of the view models.

❓ Why do we split our coordinators into two parts? In SwiftUI, we have two different responsibilities to be taken care of by a coordinator: A view's context needs to be controlled by a View that is part of the view hierarchy. But we do not have control of a view's lifecycle. This can be achieved easily with an ObservableObject. We can easily pass it around by reference and make it conform to the Identifiable protocol.

You can get more details here: https://quickbirdstudios.com/blog/coordinator-pattern-in-swiftui/