Playing with "global router-style" navigation in SwiftUI

ContentView.swift

//
//  ContentView.swift
//  AppRouterPlayground
//
//  Created by Ben Cardy on 22/02/2023.
//

import SwiftUI


enum Route: Hashable {
    case firstDestination
    case secondDestinationWithID(id: String)
}


@MainActor
class RoutePath: ObservableObject {
    @Published var path: [Route] = []
    public func navigate(to route: Route) {
        path.append(route)
    }
    public func replace(with routes: [Route]) {
        path = routes
    }
}


struct FirstDestination: View {
    @EnvironmentObject var routePath: RoutePath
    var body: some View {
        ScrollView {
            Text("First Destination")
            Button(action: {
                routePath.navigate(to: .secondDestinationWithID(id: "ID 2"))
            }) {
                Text("Go To Second Destination")
            }
        }
        .navigationTitle("First Destination")
    }
}


struct SecondDestination: View {
    @EnvironmentObject var routePath: RoutePath
    let id: String
    var body: some View {
        ScrollView {
            Text("Second Destination: \(id)")
            Button(action: {
                routePath.navigate(to: .firstDestination)
            }) {
                Text("Go To First Destination")
            }
            Button(action: {
                routePath.replace(with: [.firstDestination, .firstDestination])
            }) {
                Text("Replace!")
            }
        }
        .navigationTitle("Second \(id)")
    }
}


@MainActor
extension View {
    func withAppRouter() -> some View {
        navigationDestination(for: Route.self) { destination in
            switch destination {
            case .firstDestination:
                FirstDestination()
            case let .secondDestinationWithID(id):
                SecondDestination(id: id)
            }
        }
    }
}


struct TabOne: View {
    @StateObject private var routePath = RoutePath()
    var body: some View {
        NavigationStack(path: $routePath.path) {
            ScrollView {
                Text("Tab One")
                Button(action: {
                    routePath.navigate(to: .firstDestination)
                }) {
                    Text("Go To First Destination")
                }
                Button(action: {
                    routePath.navigate(to: .secondDestinationWithID(id: "ID 1"))
                }) {
                    Text("Go To Second Destination")
                }
            }
            .navigationTitle("Tab One")
            .withAppRouter()
        }
        .environmentObject(routePath)
    }
}


struct ContentView: View {
    var body: some View {
        TabView {
            TabOne()
                .tag(1)
                .tabItem {
                    Label("Tab One", systemImage: "1.circle")
                }
            TabOne()
                .tag(2)
                .tabItem {
                    Label("Tab Two", systemImage: "2.circle")
                }
        }
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}