NavigationStack programatically appending childviews with different types

Question

I have a NavigationStack with parent view

struct MainDatabaseView: View {
@State private var path = NavigationPath()

var body: some View {
    NavigationStack(path: $path) {
        List {
            Section {
                NavigationLink(destination: MainTabPilotDatabaseView(path: $path)) {
                    Label("Pilots", systemImage: "person.2")
                        .foregroundStyle(.primary)
                }

                NavigationLink(destination: MainTabAircraftDatabaseView()) {
                    Label("Aircraft", systemImage: "airplane.circle")
                        .foregroundStyle(.primary)
                }
                
            } header: {
                Text("Database")
            }
        }
    }
}

And a child view

struct MainTabPilotDatabaseView: View {
    @EnvironmentObject var pilotVM: PilotVM

    @Binding var path : NavigationPath

    var body: some View {
        List {
            ForEach(pilotVM.filteredPilots, id: \.id) { pilot in
                NavigationLink {
                    PilotDatabaseDetailView(pilot: pilot)
                } label: {
                    PilotCell(pilot: pilot, isInDetailView: false)
                        .contentShape(Rectangle())
                        .swipeActions(edge: .trailing) { delete(for: pilot) }
                        .swipeActions(edge: .leading) { markFavorite(for: pilot) }
                }
            }
        }
    
        .toolbar {
            ToolbarItem(placement: .topBarTrailing) { addPilot() }
        }
    }

    func addPilot() -> some View {
        Button {
            let pilotModelInput = PilotModelInput()
            let new = pilotVM.addPilotToModel(input: pilotModelInput)
            path.append(new)
        } label: {
            Image(systemName: "plus.circle.fill")
        }
      
    }
}

When I have path as @State var path: [PilotEntity] = [] the code works as expected - i.e. when plus.circle.fill button in child view is tapped, it pushes a sub-child view in the NavigationStack. However since I will also be using a different entity (AircraftEntity) for the other view in the NavigationStack, I presume that I have to go with generic NavigationPath.

I have the code mock as above and cannot seem to pass the data to the sub-child view. What is the best way of going about it?

EDIT:

I have been playing with the solution from @son and found that this also works:

import SwiftUI

enum DatabaseTabOption {
    case pilot, aircraft
}

class NavigationStackManager: ObservableObject {
    @Published var path = NavigationPath()
}

struct MainDatabaseView: View {
    @StateObject var pathManager = NavigationStackManager()

    var body: some View {
        NavigationStack(path: $pathManager.path) {
            List {
                Section {
                    NavigationLink(value: DatabaseTabOption.pilot) {
                        Button {
                            pathManager.path.append(DatabaseTabOption.pilot)
                        } label: {
                            Label("Pilots", systemImage: "person.2")
                        }
                    }

                    NavigationLink(value: DatabaseTabOption.aircraft) {
                        Button {
                            pathManager.path.append(DatabaseTabOption.aircraft)
                        } label: {
                            Label("Aircraft", systemImage: "airplane.circle")
                        }
                    }
                } header: {
                    Text("Database")
                }
            }
            .navigationDestination(for: DatabaseTabOption.self, destination: { value in
                switch value {
                case .pilot:
                    MainTabPilotDatabaseView()
                        .environmentObject(pathManager)
                case .aircraft:
                    MainTabAircraftDatabaseView()
                        .environmentObject(pathManager)
                }
            })
        }
    }
}

I am passing enum on the parent level. I am wrapping the Buttons in NavigationLink in order to get the navigation prompts (chevrons) back. In child view I can then append any other type to the path. Thanks to @son for steering me onto the right path.

Answer 1

NavigationPath can append generic type which conforms Hashable. So you can totally add AircraftEntity since this model conforms to the Hashable protocol. And change .navigationDestination for this type.

List {
    ForEach(pilotVM.filteredPilots, id: \.id) { pilot in
        Button {
            path.append(pilot)
        } label: {
            PilotCell(pilot: pilot, isInDetailView: false)
                .contentShape(Rectangle())
                .swipeActions(edge: .trailing) { delete(for: pilot) }
                .swipeActions(edge: .leading) { markFavorite(for: pilot) }
        }
        ...
    }
}
.navigationDestination(for: PilotEntity.self) { pilot in
    PilotDatabaseDetailView(pilot: pilot)
}

Also, multiple types in the same context:

NavigationStack(path: $path) {
    List {
        Section {
            Button {
                path.append("Pilot") //<- put something to recognize Pilot
            } label: {
                Label("Pilots", systemImage: "person.2")
                    .foregroundStyle(.primary)
            }
            
            Button {
                path.append(111) //<- put something to recognize Aircraft
            } label: {
                Label("Aircraft", systemImage: "airplane.circle")
                    .foregroundStyle(.primary)
            }
        } header: {
            Text("Database")
        }
    }
    .navigationDestination(for: String.self) { text in
        //Pilot
    }
    .navigationDestination(for: Int.self) { num in
        //Aircraft
    }
}