未處理的例外：型別'(String,int)=>Future<Null>'不是型別轉換中型別'(String,int?)=>void'的

需要幫助來解決這個問題，我在運行我的代碼時遇到了這個問題。它一直顯示這個錯誤未處理的例外：型別'（字串，int）=>未來'不是型別轉換中的'（字串，int？）=> void'型別的子型別..我嘗試解決這個問題無濟于事，我去了各種論壇，看到了不同的想法，但這些想法并不適用。我希望有人可以幫助我。

class AuthProvider with ChangeNotifier {

  FirebaseAuth _auth = FirebaseAuth.instance;
  late String smsOtp;
  late String verificationId;
  String error = '';
  UserServices _userServices = UserServices();

  Future < void > verifyPhone(BuildContext context, String number) async {
    final PhoneVerificationCompleted verificationCompleted =
      (PhoneAuthCredential credential) async {
        await _auth.signInWithCredential(credential);
      };

    final PhoneVerificationFailed verificationFailed = (FirebaseAuthException e) {
      print(e.code);
    };

    final PhoneCodeSent smsOtpSend = (String verId, int resendToken) async {
      this.verificationId = verId;
    }
    as PhoneCodeSent;

    smsOtpDialog(context, number);

    try {
      _auth.verifyPhoneNumber(
        phoneNumber: number,
        verificationCompleted: verificationCompleted,
        verificationFailed: verificationFailed,
        codeSent: smsOtpSend,
        codeAutoRetrievalTimeout: (String verId) {
          this.verificationId = verId;
        },
      );

    } catch (e) {
      print(e);
    }
  }

  Future < bool ? > smsOtpDialog(BuildContext context, String number) {
    return showDialog(
      context: context,
      builder: (BuildContext context) {
        return AlertDialog(
          title: Column(
            children: [
              Text('Verification Code'),
              SizedBox(height: 6, ),
              Text('Enter the 6 didgit Code received by sms',
                style: TextStyle(color: Colors.grey, fontSize: 10),
              ),
            ],
          ),
          content: Container(
            height: 85,
            child: TextField(
              textAlign: TextAlign.center,
              keyboardType: TextInputType.number,
              maxLength: 6,
              onChanged: (value) {
                this.smsOtp = value;
              },
            ),
          ),
          actions: [
            FlatButton(
              onPressed: () async {
                (context);
                try {
                  PhoneAuthCredential phoneAuthCredential =
                    PhoneAuthProvider.credential(
                      verificationId: verificationId,
                      smsCode: smsOtp,

                    );

                  final User ? user = (await _auth.signInWithCredential(phoneAuthCredential)).user;

                  //create user data in fireStore after successful login
                  _createUser(id: user!.uid, number: user.phoneNumber ? ? "");
                  //navigate to homepage after login
                  if (user != null) {
                    Navigator.of(context).pop();

                    //dont want to come back to welcome screen after login
                    Navigator.of(context).pushReplacement(MaterialPageRoute(
                      builder: (context) => HomeScreen(),
                    ));
                  } else {
                    print('Login Failed');
                  }

                } catch (e) {
                  this.error = 'Invalid Code';
                  print(e.toString());
                  notifyListeners();
                  Navigator.of(context).pop();
                }
              },
              child: Text('DONE', style: TextStyle(color: Theme.of(context).primaryColor), ),
            ),
          ],
        );
      });
  }

  void _createUser({
    required String id,
    required String number
  }) {
    _userServices.createUserData({
      'id': id,
      'number': number,
    });
  }
}

uj5u.com熱心網友回復：

改變

final PhoneCodeSent smsOtpSend = (String verId, int resendToken) async {
      this.verificationId = verId;
    }

到

final PhoneCodeSent smsOtpSend = (String verId, int? resendToken) {
      this.verificationId = verId;
    }

回呼型別int?不是int，注意空安全的問號。并洗掉async關鍵字，因為它是一個常規函式，而不是未來。

標籤：扑 镖

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