How to bind an action to the navigationview back button?

Question

I would like to bind an action to the Back button in the navigationview toolbar, is it possible?

var body: some View {
     List {
          ForEach(mainViewModel.items) { item in
              NavigationLink(destination: EditTaskView(item: item)) {
                  HStack {
                      ListRowView(item: item)
                  }
              }
         }
     }
}

Answer 1

You can't bind directly to the back button, but you can have the navigation link itself be activated based on state, and then listen to the change of the state value like so. Do note that this requires that you manage the setting of state to true (no auto tap like with the default initializer)

struct ContentView: View {
  @State private var showingNavView = false
  var body: some View {
    NavigationView {
      List {
        NavigationLink("Sub View", isActive: $showingNavView) {
          SubView()
        }.onTapGesture {
          showingNavView = true
        }.onChange(of: showingNavView) { newValue in
          print(newValue) // Will change to false when back is pressed
        }
      }
    }
  }
}
struct SubView: View {
  var body: some View {
    ZStack {
      Color.green
      Text("Cool Beans")
    }
  }
}