Is it possible to use Decompose with SwiftUI NavigationLink?

[plusmobileapps]

I was integrating Decompose into an iOS app and was wondering if it's possible to use the NavigationLink from SwiftUI to achieve the native back swipe gesture and toolbar? I applied a simple example to the todo app using NavigationLink.

struct MainView: View {
    private let component: TodoMain
    
    @ObservedObject
    private var models: ObservableValue<TodoMainModel>
    
    init(_ component: TodoMain) {
        self.component = component
        self.models = ObservableValue(component.models)
    }
    
    var body: some View {
        let model = models.value
        
        return NavigationView {
            VStack {
                // how would the new component get to the destination parameter? 
                NavigationLink(destination: Text("View2").navigationBarTitle("Title View2", displayMode: .inline)) {
                      Text("NavigationLink") 
                  }
                ListView(
                    items: model.items,
                    onItemClicked: component.onItemClicked,
                    onDoneChanged: component.onItemDoneChanged
                )

                InputView(
                    textBinding: Binding(get: { model.text }, set: component.onInputTextChanged),
                    onAddClicked: component.onAddItemClicked
                )
            }.navigationBarTitle("Todo Sample", displayMode: .inline)
        }
    }
}

Using the code above, I understand that the current RootView supplies the components to each individual component and was not quite how to supply the new component to the NavigationLink? 🤔

Any help would be greatly appreciated or if there is a different way of achieving the native gesture without NavigationLink

[arkivanov]

First of all, I'm not quite familiar with SwiftUI. As far as I know, NavgiationLink should be put around each item. I found the following links, which look useful:

• https://www.hackingwithswift.com/quick-start/swiftui/how-to-push-a-new-view-when-a-list-row-is-tapped
• https://www.simpleswiftguide.com/how-to-add-navigationview-to-list-in-swiftui-and-show-detail-view-using-navigationlink/

But as far as I know, NavigationLink is active component. It accepts a View, and SwiftUI displays it inside NavigationView. Looks like in this case the navigation is managed by SwiftUI, however ideally it should be managed by Decompose. It's like still using Fragments in Android. So if possible, I would avoid NavigationLink and use NavigationView instead, as in the TodoApp example.

Also when I was playing with NavigationLink in MVIKotlin, I found that it creates views eagerly. So for N items in the list (and so N NavigationLinks), it was immediately creating N detail views. So I found a workaround with LazyView.

[plusmobileapps]

Thanks for the response, NavigationLink does seem to go against the idea behind Decompose since it using SwiftUI's navigation. I did see that iOS example on MVIKotlin utilizes NavigationLink to achieve the native back swipe gesture, but I do like the concept behind Decompose consolidating routing logic.

I wonder if there is another way to hook into the back swipe gesture on SwiftUI with Decompose without using NavigationLink? 🤔

[arkivanov]

Again, I have little experience with SwiftUI, but I would try the following. A while ago, when the TodoApp example was in this repository, it contained the RouterView. This view just renders all child views in ZStack, one on top another. This solved the issue with UI state preservation when navigating back (e.g. scroll position). So I would try to use this view for the swiping as well. The gesture recognition and swiping perhaps should be done using SwiftUI, hope there is a way of doing it. And when the top view is swiped out, just call a function on your component so it will pop the stack. Hope this helps.