MyViewModel.kt

class MyViewModel(authManager..., repository...) : ViewModel() {
    private val userId: Flow<UserId> = authManager.observeUser().map { user -> user.id }

    val result: StateFlow<Result<Item>> = userId.mapLatest { newUserId ->
        repository.fetchItem(newUserId)
    }.stateIn(
        scope = viewModelScope, 
        started = WhileSubscribed(5000), 
        initialValue = Result.Loading
    )
}