Navigation link modifier

[HugoSay]

Hello!

On the project I'm currently working on, we can navigate to a view hierarchically even though we don't have any NavigationLink visible on the screen.

I came up with these two operators to add some invisible navigation links with the same kind of declaration as the one used for sheets.

How do you feel about these ? :)

extension View {
    func navigation<Enum, Case, WrappedDestination: View>(
        unwrapping: Binding<Enum?>,
        case: CasePath<Enum, Case>,
        @ViewBuilder destination: @escaping (Binding<Case>) -> WrappedDestination,
        onNavigate: @escaping (Bool) -> Void) -> some View {
            self.background(
                NavigationLink(unwrapping: unwrapping, case: `case`, destination: destination, onNavigate: onNavigate) {
                    EmptyView()
                }
            )
        }

    func navigation<Enum, WrappedDestination: View>(
        unwrapping: Binding<Enum?>,
        @ViewBuilder destination: @escaping (Binding<Enum>) -> WrappedDestination,
        onNavigate: @escaping (Bool) -> Void) -> some View {
            self.background(
                NavigationLink(unwrapping: unwrapping, destination: destination, onNavigate: onNavigate) {
                    EmptyView()
                }
            )
        }
}

*Edited to use the background modifier as suggested in answers
Here is an example of usage:

struct Test: View {
    enum Route {
        case a,b,c,d
    }
    @State var selected: Route? = nil

    var body: some View {
        NavigationView {
            List {
                // obviously, in this case navigation links instead of buttons could also work just fine :)
                Button("a") { selected = .a }
                Button("b") { selected = .b }
                Button("c") { selected = .c }
                Button("d") { selected = .d }
            }
            .navigation(unwrapping: $selected) { route in
                viewForRoute(route.wrappedValue)
            } onNavigate: { isActive in
                if isActive == false { selected = nil }
            }
            .navigationTitle("Hidden Navigation Link")

        }
    }

    @ViewBuilder
    func viewForRoute(_ route: Route) -> some View {
        switch route {
        case .a: Text("A")
        case .b: Text("B")
        case .c: Text("C")
        case .d: Text("D")
        }
    }
}

Cheers!

[mbrandonw]

Hi @HugoSay, this is a really cool extension, and glad that the tools in this library could help implement it!

We are a little hesitant on adding such a tool directly to the library for a few reasons:

• Currently the library is focused on recreating Apple's navigation APIs in a style that is better suited for optional and enum state. Since Apple doesn't ship a view modifier style of navigation we think maybe it shouldn't be added to this library.
• We also aren't 100% confident about the repercussions of hiding navigation links like this. We know people do it often, but we have personally seen weird side effects depending on the manner in which you hide it (such as extra spacing showing up where you don't want it). There are also other styles of hiding, such as .background { NavLink { EmptyView } }, but again we don't know the repercussions of doing that.

But, all of that is to say that we totally agree this tool can be extremely handy, but it just may not be appropriate for the library as of right now. Perhaps in the future we will expand its scope. 🙂

[HugoSay]

I see your point, hopefully anyone in need for this extension will find this discussion easily 🙂
The library made it super easy to implement it though, so I think I'm not the first to do so !

I'll use this .background() method, it seems nicer than the VStack 👍

Thanks for the great work you guys do !

[AlexisQapa]

IIRC I switched to background style when hiding navigation links due to bugs (including mostly spacing as said when embedding VStack to another Stack without the same spacing)