I have a NavigationView and it has 3 views I want to navigate to successively. Each view has a NavigationLink within it. Ideally, I want:

View 1 -> View 2 -> View 3

But what I get is: View 1 -> View 2 -> View 3 (1sec) -> View 1

I am using the tagged selection method for the NavigationLink, and the selection is from a @Published EnvironmentObject.

Here's the code:

import SwiftUI

struct ContentView: View {
    
    @EnvironmentObject var viewModel: ViewModel

    var body: some View {
        
        VStack {
            NavigationLink(destination: secondPage(), tag: "View 2", selection: $viewModel.selection) {
                Button(
                    action: {
                        viewModel.selection = "View 2"
                    }, label: {
                        Text("view 2")
                    }
                )
                .navigationTitle("View 1")
            }
            .isDetailLink(false)
        }
    }
}



struct secondPage: View {
    
    @EnvironmentObject var viewModel: ViewModel
    
    var body: some View {

        NavigationLink(destination: thirdPage(), tag: "View 3", selection: $viewModel.selection) {
            Button(
                action: {
                    viewModel.selection = "View 3"
                },
                label: {
                    Text("View 3")
                }
            )
            .navigationTitle("View 2")
        }
        .isDetailLink(false)
    }
}


struct thirdPage: View {
    
    var body: some View {
        VStack {
            Text("third page")
        }
        .navigationTitle("View 3")
    }
}

class ViewModel: ObservableObject {
    @Published var selection: String? = nil
}

import SwiftUI

@main
struct testApp: App {
    
    @StateObject var viewModel = ViewModel()
    
    var body: some Scene {
        WindowGroup {
            NavigationView {
                ContentView()
            }
            .navigationViewStyle(StackNavigationViewStyle())
            .environmentObject(viewModel)
        }
    }
}

I use a button and the viewModel because in my real code I need the code to perform an action.

Help would be so appreciated!

CodePudding user response：

Welcome to StackOverflow! The problem you are having is very similar to this question, but you are using a different mechanism. The reason for the pop back is that you are using the same variable to handle both NavigationLinks, so, instead of:

View 1 -> View 2 -> View 3

what is actually happening is:

View 1(viewModel.selection = "View 2") -> View 2

Then, when you try to navigate again:

View 2(viewModel.selection = "View 3")

You are actually changing your original link to

View 1(viewModel.selection = "View 3") -> View 2

as well. The OS gets confused and pops back to the first link(SecondPage). To fix it, simply use multiple variables to keep the navigation state:

struct ContentView: View {
    @EnvironmentObject var viewModel: PageViewModel

    var body: some View {
        
        VStack {
            NavigationLink(destination: secondPage(), tag: "View 2", selection: $viewModel.selection2) {
                Button(
                    action: {
                        viewModel.selection2 = "View 2"
                    }, label: {
                        Text("view 2")
                    }
                )
                .navigationTitle("View 1")
            }
            .isDetailLink(false)
        }
    }
}

struct secondPage: View {
    
    @EnvironmentObject var viewModel: PageViewModel
    
    var body: some View {

        NavigationLink(destination: thirdPage(), tag: "View 3", selection: $viewModel.selection3) {
            Button(
                action: {
                    viewModel.selection3 = "View 3"
                },
                label: {
                    Text("View 3")
                }
            )
            .navigationTitle("View 2")
        }
        .isDetailLink(false)
    }
}

struct thirdPage: View {
    
    var body: some View {
        VStack {
            Text("third page")
        }
        .navigationTitle("View 3")
    }
}

class PageViewModel: ObservableObject {
    @Published var selection2: String? = nil
    @Published var selection3: String? = nil
}