Flutter Firebase 验证电话完成程序搞砸了

Question

我正在尝试使用 Firebase 验证手机。

第一次验证（第一次verifyPhoneNumberFirebase调用没问题（打开验证码，没验证按回，还是去codeSent，不知道为什么）。

但是第二次验证（第二次verifyPhoneNumberFirebase，发生在第一次验证几秒钟之后）超时，运行codeAutoRetrievalTimeout。但奇怪的是 completer 完成了，尽管它被重新启动，但前一次调用 (codeSent) 的结果。这是代码

Future<DataResponse> verifyPhoneNumberFirebase({String phoneNumb}) async {
    final completer = Completer<DataResponse>(); /// <--- init and re-init
    _auth
        .verifyPhoneNumber(
      phoneNumber: phoneNumb,
      verificationCompleted: (PhoneAuthCredential credential) {
        completer.complete(successSomething(verificationId));
      },
      verificationFailed: (FirebaseAuthException e) {
        completer.complete(errorHandling('error');
        }
      },
      codeSent: (String verificationId, int resendToken) {
        completer.complete(successSomething(verificationId)); 
         /// the first complete, 
         /// and somehow the second complete, 
         /// even though it did not go to this line in the second call
      },
      codeAutoRetrievalTimeout: (String verificationId) {
        completer.complete(errorHandling('error'); /// <----- already completed ???
      },
    );
    return completer.future;
  }

这里是日志

[ERROR:flutter/lib/ui/ui_dart_state.cc(199)] Unhandled Exception: Bad state: Future already completed
_AsyncCompleter.complete (dart:async/future_impl.dart:45:31)
...

现在我不知道如何获得codeAutoRetrievalTimeout 输出。

Answer 1

之所以出现错误，是因为您在 verificationCompleted 回调中使用了 Completer，而它已在 codeSent 回调中使用。

您可以从codeSent 块中删除completer.complete，因为此时它还没有完成操作。

以下是您的 _auth.verifyPhoneNumber 代码的更新：

     _auth
            .verifyPhoneNumber(
          phoneNumber: phoneNumb,
          verificationCompleted: (PhoneAuthCredential credential) {
            completer.complete(successSomething(verificationId));
          },
          verificationFailed: (FirebaseAuthException e) {
            completer.complete(errorHandling('error');
            }
          },
          codeSent: (String verificationId, int resendToken) {
            successSomething(verificationId); // Remove completer.complete
          },
          codeAutoRetrievalTimeout: (String verificationId) {
            completer.complete(errorHandling('error'); 
          },
        );