NavigationCoordinator

Everyone who tried to use SwiftUI’s NavigationView in a big production level app faced a problem navigating using a standard NavigationView. Of course the NavigationStack fixes the problem, but what if you can’t use NavigationStack because it is not available pre iOS 16?

With NavigationView you have to have a NavigationLink in your current View to navigate to a next View. So you have to put a NavigationLink with specific View in order to navigate there. When using a ViewModel you can’t just call push(NextView()) to show the NextView. You have to activate the NavigationLink which has to be in your current View in order to show the NextView. It is ok if you have a simple app which has exact hierarchy of views, but if you have a complicated dynamic routes such approach becomes painful.

It would be better to have a solution when you can just say which view you want to navigate to without putting all possible NavigationLinks into current view. In this case my solution comes in handy.

You just write:

coordinator.push(.profile)

And NavigationView pushes the ProfileView on to the stack. All you need is to add case profile to enum Screen and add ProfileView() into ScreenView. This way NavigationCoordinator will be able to push ProfileView onto the navigation stack without any more efforts.

The basic example is:

import SwiftUI

@main
struct NavigationApp: App {
    @StateObject var coordinator = NavigationCoordinator(rootScreen: .home)

    var body: some Scene {
        WindowGroup {
            NavigationView {
                coordinator.rootView
            }
            .environmentObject(coordinator)
        }
    }
}

This is how HomeView looks like:

import SwiftUI

struct HomeView: View {
    @EnvironmentObject private var coordinator: NavigationCoordinator
    var body: some View {
        VStack(spacing: 20) {
            Button("Go to Profile") {
                coordinator.push(.profile)
            }
            Button("Go to Settings") {
                coordinator.push(.settings)
            }
        }
        .navigationTitle("Home")
    }
}

That’s it! You can now build a complicated hierarchy of navigation in your app. And it is compatible with MVVM approach.

NavigationController alternative

Or you can take my alternative version which enables you to specify any View to navigate to inline:

controller.push(ProfileView())

But this version relies on AnyView which is dangerous. Apple Engineers don’t recommend to use AnyView because it has performance issues and may have other unexpected issues. Use NavigationController variant cautious.