FirebaseAuth - 我如何等待价值

Question

我使用 FirebaseAuth 注册新用户

class FirebaseAuthenticationServiceImpl(): FirebaseAuthenticationService {
        
            override fun registerWithEmailAndPassword(email: String, password: String): Boolean {

                val registration = FirebaseAuth.getInstance().createUserWithEmailAndPassword(email, password)
                    .addOnSuccessListener {
                        println(it.additionalUserInfo?.providerId.toString())
                    }.addOnFailureListener {
                        println(it.message.toString())
                    }
                return registration.isSuccessful
            }
}

我每次都调用上面的函数 false。一段时间后我得到 true

    coroutineScope {
                try {
                    if (firebaseService.registerWithEmailAndPassword(email, password)) {
                        openHomeActivity.offer(Unit)
                    } else {}
                } catch (e: Exception) {}
   }

我如何才能等待结果 (success/failure) 并获得该值？

Answer 1

FirebaseAuthenticationService 来自哪里？你需要它吗？官方入门指南只是使用Firebase.auth。有了这个，您可以使用 await() 挂起函数而不是使用回调方法进行身份验证。

// In a coroutine:
val authResult = Firebase.auth.registerWithEmailAndPassword(email, password).await()
val user: FirebaseUser = authResult.user
if (user != null) {
    openHomeActivity.offer(Unit)
} else {
    // authentication failed
}

Answer 2

如果您正在使用协同程序，您可以使用 suspendCoroutine，它是传统回调和协同程序之间的完美桥梁，因为它使您可以访问 Continuation<T> 对象，例如 Task<R> 个对象：

    scope.launch {
    
       val registrationResult = suspendCoroutine { cont -> cont.suspendTask(FirebaseAuth.getInstance().createUserWithEmailAndPassword(email, password) }
    
    }
    
    private fun <R> Continuation<R>.suspendTask(task: Task<R>) {
            task.addOnSuccessListener { this.success(it) }
                .addOnFailureListener { this.failure(it) }
        }

    private fun <R> Continuation<R>.success(r : R) = resume(r)
    private fun <R> Continuation<R>.failure(t : Exception) = resumeWithException(t)

FirebaseAuth - 我如何等待价值

FirebaseAuth - how can I wait for value

android

kotlin

firebase

firebase-authentication

kotlin-coroutines