SwiftUI: Replacing window dismisses only topmost modal view

Question

I need to show a login screen when the user session is expired. I tried to achieve this by changing the current window:

@main
struct ResetViewHierarchyApp: App {
    
    @StateObject private var state = appState
        
    var body: some Scene {
        WindowGroup {
            if state.isLoggedIn {
                ContentView()
            } else {
                LogInView()
            }
        }
    }
}

When no modal views are presented then it works fine. If only one modal view is presented, it also works, the modal view is dismissed. But if there are more than one modal views are presented, then the root view is replaced, but only the topmost modal view is dismissed. Here is ContentView:

struct ContentView: View {
    
    @State private var isPresentingSheet1 = false
    @State private var isPresentingSheet2 = false
    
    var body: some View {
        Text("Hello, world!")
            .padding()
        
        Button(action: {
            isPresentingSheet1 = true
        }, label: {
            Text("Present Sheet")
                .padding()
        }).sheet(isPresented: $isPresentingSheet1) {
            sheetView1
        }
    }
}

private extension ContentView {
    
    var sheetView1: some View {
        VStack {
            Text("Sheet 1")
                .padding()
            Button(action: {
                isPresentingSheet2 = true
            }, label: {
                Text("Present Sheet")
                    .padding()
            }).sheet(isPresented: $isPresentingSheet2) {
                sheetView2
            }
        }
    }
    
    var sheetView2: some View {
        VStack {
            Text("Sheet 2")
                .padding()
            Button(action: {
                appState.isLoggedIn = false
            }, label: {
                Text("Log Out")
                    .padding()
            })
        }
    }
}

The same happens if I use fullScreenCover instead of sheet.

Does anybody know how to solve this issue, to dismiss all the presented modals at once?

Answer 1

I've solved this issue with UIKit windows:

@StateObject private var state = appState @State private var contentWindow: UIWindow?

var body: some Scene {
    WindowGroup {
        EmptyView()
            .onAppear {
                updateContentWindow(isLoggedIn: state.isLoggedIn)
            }.onReceive(state.$isLoggedIn) { isLoggedIn in
                updateContentWindow(isLoggedIn: isLoggedIn)
            }
    }
}

var window: UIWindow? {
    guard let scene = UIApplication.shared.connectedScenes.first,
          let windowSceneDelegate = scene.delegate as? UIWindowSceneDelegate,
          let window = windowSceneDelegate.window else {
        return nil
    }
    
    return window
}

func updateContentWindow(isLoggedIn: Bool) {
    contentWindow?.isHidden = true
    contentWindow = nil
    
    if let windowScene = window?.windowScene {
        contentWindow = UIWindow(windowScene: windowScene)
        contentWindow?.windowLevel = UIWindow.Level.normal
        if isLoggedIn {
            contentWindow?.rootViewController = UIHostingController(rootView: ContentView())
        } else {
            contentWindow?.rootViewController = UIHostingController(rootView: LogInView())
        }
        
        contentWindow?.makeKeyAndVisible()
    }
}