FUIAuthDelegate is not called if the view is activated in a .sheet

[acgacgacgacg]

Similar to #1198
I use the FirebaseAuthUI in SwiftUI. I wrapped it in a UIViewControllerRepresentable and implemented the makeCoordinator method to set the delegate like the following

struct AuthView: View {
  var body: some View {
    AuthViewControllerRepresentable()
  }
}

struct AuthViewControllerRepresentable: UIViewControllerRepresentable {
  ...
  func makeCoordinator() -> Coordinator {
    Coordinator()
  }

  func makeUIViewController(context: Context) -> UINavigationController {
    let authUI = FUIAuth.defaultAuthUI()!
    authUI.delegate = context.coordinator
    ...
  }

  class Coordinator: NSObject, FUIAuthDelegate {
    func authUI(
      _ authUI: FUIAuth, didSignInWith authDataResult: AuthDataResult?, error: Error?
    ) {
      print("authUI called")
      }
  }
}

The FUIAuthDelegate is not called if it is activated inside a .sheet like the following

.sheet(isPresented: $showAuthViewSheet) {
      AuthView()
    }

However, the FUIAuthDelegate method will get called if it is a stand alone page.

I'm using v14.2.6

[morganchen12]

My guess is this is because the UIViewControllerRepresentable is deallocated before the delegate method is invoked. The AuthUI instance doesn't strongly retain its delegate.

We're working on a SwiftUI-native auth flow which you can try out here, though it's lacking UI design and feature parity with the current FirebaseAuthUI.