Best way to handle a TabView inside a NavigationView in SwiftUI

I am developing an app in Swift with SwiftUI.

I have this setup where I put a TabView inside a NavigationView and used the navigationBarTitle on the tabView. I did this because if I put the NavigationView inside the TabView, I cannot make the Tab bar disappear when I go to a NavigationLink: it seems currently impossible with swiftUI.

The current problem with my setup is that since I put the .navigationBarTitle on the TabView, the title does not change when I change the tab view and I cannot reset the .navigationBarTitle on the subview for some reason.

Here is a code to explain what I am saying:

ContentView :

NavigationView {
  TabView {
    SomeSubView().tabItem() { Text("SomeSubView") }
    Text("dummy2").tabItem() { Text("dummy2") }
    Text("dummy3").tabItem() { Text("dummy3") }
  }.navigationBarTitle("hello")
}

SomeSubView:

List(somearray) { element in
  NavigationLink(destination: elementDetails()) {
    SomeRowView()
  }
}

Here is a preview (the code above isn't exactly my code but just an example):

Preview

Now I woukd like to put the .navigationBarTitle inside the SomeSubView() like this:

List(somearray) { element in
  NavigationLink(destination: elementDetails()) {
    SomeRowView()
  }
}.navigationBarTitle("title2")

Instead of choosing a global title for the TabView. So in that case I would have something like:

NavigationView {
  TabView {
    SomeSubView().tabItem() { Text("SomeSubView") }
  }
}

Then I choose a .navigationBarTitle inside the SomeSubView() but it doesn't work (the title bar just does not appear, instead the tab title is changed and that's not what I want).

So I finally came up with this kind of setup:

@State private var title = Text("Default_Title")

var body: some View {
  NavigationView {
    TabView {
      SomeSubView().tabItem { Text("SomeSubView") }.onAppear { self.title = Text("new_title") }
      Text("dummy2").tabItem { Text("dummy2") }
      Text("dummy3").tabItem { Text("dummy3") }
    }.navigationBarTitle(title)
  }
}

This way, I can dynamically change the title when I click on a tab view and it works fine but I also need to set different .navigationBarItems for each tab view so I did the same thing for the leading and trailing parameters of .navigationBarItems, like this:

@State private var title = Text("Default_Title")
@State private var leading = NavBar_leading(type: "FirstView")
@State private var trailing = NavBar_trailing(type: "FirstView")

var body: some View {
  NavigationView {
    TabView {
      SomeSubView().tabItem { Text("SomeSubView") }.onAppear {
          self.title = Text("new_title")
          self.leading = NavBar_leading(type: "FirstView")
          self.trailing = NavBar_trailing(type: "FirstView")
      }
      Text("dummy2").tabItem { Text("dummy2") }
      Text("dummy3").tabItem { Text("dummy3") }
    }.navigationBarTitle(title).navigationBarItems(leading: leading, trailing: trailing)
  }
}

As you can see, I dynamically update the leading and trailing parameters of .navigationBarItems to set different items (buttons in my case) for each tab view. The NavBar_leading and NavBar_trailing view return a Button text type depending on the parameter I passed, like this:

struct NavBar_leading: View {
    var type: String
    
    var body: some View {
        if type == "FirstView" {
            return Button(action: {
                print("hello1 empty")
                }) {
                    Text("")
            }
        } else if (type == "SecondView") {
            return Button(action: {
                print("hello2")
                }) {
                    Text("SomeButton")
            }
        } else {
            return Button(action: {
                print("hello3 empty")
                }) {
                    Text("")
            }
        }
    }
}

Now the problem is that I want to return sometimes a Button Text, but sometimes a Button Image from the same NavBar_leading view but Swift does not allow me to have different types returned from the same view. I thought the Button view was one type but it seems that depending on what you put inside, it becomes another type.

I heard that the Any view type isn't a good practice in Swift and has performance impact, so I'm looking for a way to achieve what I want here.

I explained everything because I am open to any other suggestion, like if I can do something totally better I am open to restart from scratch, so here are my questions:

Is my handling with the TabView inside the NavigationView a good idea for what I needed to do? Is there something better that I do not know?
Is there any other way to display a different title for each tab view instead of a global title that I update like I did?
Is there any way to return different Button types from a view without using an Any view type? Anything better that I can do?

Thank you

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