我尝试使用firebase创建一个livedata，但由于某种原因，我在使用此语句"_loginFlow. value = result"时收到一个错误-它说："要求：FirebaseUser〉？，找到：Firebase用户〉
是什么导致的？任何帮助都是感激的!
我的代码：

private val _loginFlow = MutableStateFlow<Resource<FirebaseUser>?>(null)
val loginFlow: StateFlow<Resource<FirebaseUser>?> = _loginFlow


    fun loginUser(email: String, password: String) = viewModelScope.launch {
    _loginFlow.value = Resource.Loading
    val result = repository.login(email, password)
    _loginFlow.value = result
}

@Composable
fun LoginButton(onClick: () -> Unit) {

   // LOGIN BUTTON
 Spacer(modifier = Modifier.height(20.dp))
        Box(modifier = Modifier.padding(40.dp, 0.dp, 40.dp, 0.dp)) {
                        Button(
                            onClick = {
                                viewModel?.loginUser(email, password)
                            },
                            shape = RoundedCornerShape(50.dp),
                            modifier = Modifier
                                .fillMaxWidth()
                                .height(50.dp)
                        ) {
                            Text(text = "Login")
                        }
                    }

验证存储库：

interface AuthRepository {
    val currentUser: FirebaseUser?
    suspend fun login(email: String, password: String): Resource<FirebaseUser>
    suspend fun signup(name: String, email: String, password: String): Resource<FirebaseUser>
    fun logout()
}

资源：

sealed class Resource<out R> {
    data class Success<out R>(val result: R) : Resource<R>()
    data class Failure(val exception: Exception) : Resource<Nothing>()
    object Loading : Resource<Nothing>()
}