Swiftui Multiple Navigationlinks in Form/Sheet - Entry Stays Highlighted

SwiftUI prevent List in Sheet from inheriting parent Form styles

Use DefaultListStyle()

ListView().listStyle(DefaultListStyle())

TabView resets navigation stack when switching tabs

Here's a simple example of how to preserve state for a navigation stack with a list of items at the root:

struct ContentView: View {

    var body: some View {

        TabView {

            Text("First tab")
                .tabItem { Image(systemName: "1.square.fill"); Text("First") }
                .tag(0)

            SecondTabView()
                .tabItem { Image(systemName: "2.square.fill"); Text("Second") }
                .tag(1)
        }
    }
}

struct SecondTabView: View {

    private struct ListItem: Identifiable {
        var id = UUID()
        let title: String
    }

    private let items = (1...10).map { ListItem(title: "Item #\($0)") }

    @State var selectedItemIndex: Int? = nil

    var body: some View {

        NavigationView {
            List(self.items.indices) { index in
                NavigationLink(destination:  Text(self.items[index].title),
                               tag: index,
                               selection: self.$selectedItemIndex) {
                    Text(self.items[index].title)
                }
            }
            .navigationBarTitle("Second tab", displayMode: .inline)
        }
    }
}

SwiftUI's NavigationLink `tag` and `selection` in NavigationView stops working if not all NavigationLinks are displayed

This happens because lower items are not rendered, so in the hierarchy there's no NavigationLink with such tag

I suggest you using an ZStack + EmptyView NavigationLink "hack".

Also I'm using LazyView here, thanks to @autoclosure it lets me pass upwrapped currentSelection: this will only be called when NavigationLink is active, and this is happens when currentSelection != nil

struct ContentView: View {
    @State var entries = [10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25]
    @State var currentSelection: Int? = nil

    var body: some View {
        NavigationView {
            ZStack {
                EmptyNavigationLink(
                    destination: { DetailView(entry: $0) },
                    selection: $currentSelection
                )
                Form {
                    ForEach(entries.sorted(), id: \.self) { entry in
                        NavigationLink(
                            destination: DetailView(entry: entry),
                            label: { Text("The number \(entry)") })
                    }
                }
                .toolbar {
                    ToolbarItem(placement: ToolbarItemPlacement.navigationBarLeading) { Button("Add low") {
                        let newEntry = (entries.min() ?? 1) - 1
                        entries.insert(newEntry, at: 1)
                        currentSelection = newEntry
                    } }
                    ToolbarItem(placement: ToolbarItemPlacement.navigationBarTrailing) { Button("Add high") {
                        let newEntry = (entries.max() ?? 50) + 1
                        entries.append(newEntry)
                        currentSelection = newEntry
                    } }
                    ToolbarItem(placement: ToolbarItemPlacement.bottomBar) {
                        Text("The current selection is \(String(describing: currentSelection))")
                    }
                }
            }
        }
    }
}

struct DetailView: View {
    let entry: Int
    var body: some View {
        Text("It's a \(entry)!")
    }
}

public struct LazyView<Content: View>: View {
    private let build: () -> Content
    public init(_ build: @autoclosure @escaping () -> Content) {
        self.build = build
    }
    public var body: Content {
        build()
    }
}

struct EmptyNavigationLink<Destination: View>: View {
    let lazyDestination: LazyView<Destination>
    let isActive: Binding<Bool>
    
    init<T>(
        @ViewBuilder destination: @escaping (T) -> Destination,
        selection: Binding<T?>
    )  {
        lazyDestination = LazyView(destination(selection.wrappedValue!))
        isActive = .init(
            get: { selection.wrappedValue != nil },
            set: { isActive in
                if !isActive {
                    selection.wrappedValue = nil
                }
            }
        )
    }
    
    var body: some View {
        NavigationLink(
            destination: lazyDestination,
            isActive: isActive,
            label: { EmptyView() }
        )
    }
}

Check out more about LazyView, it helps often with NavigationLink: in real apps destination may be a huge screen, and when you have a NavigationLink in each cell SwiftUI will process all of them which may lead to lags

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