Question 78980 in Flutter Question posted in
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type 'Null' is not a subtype of type 'String' – Flutter

i am getting this error in login fuction

void _login() async {
  var user = LoginUser(
    emailId: _emailController.text,
    password: _passwordController.text,
  );

  try {
    CustomerLoginResponse response =
        await ApiManager().loginUser(user).catchError((err) {
      return Future<CustomerLoginResponse>.error(err);
    });

    if (response.successful) {
      showDataAlert();
      print(response.message);
    } else {
      print(response.message);
    }
  } catch (e) {
    print(e);
  }
}

error i am getting :
I/flutter ( 5362): type ‘Null’ is not a subtype of type ‘String’

Tags:

2

Answers


  1. 0

    If you’re only get the error when credentials are wrong, then LoginUser is returning null and it’s expecting a string. I would declare user as String? user = LoginUser… Again, all this is somewhat inference because you’re not providing full info to know for sure. Then you need to null check user. User an if/then to ensure that if (user != null)....

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  2. 0

    This error message typically indicates that you are trying to assign a value of type Null to a variable or field that expects a value of type String.

    To fix this error, you will need to make sure that the value you are trying to assign to a variable or field is of the correct type. If you want to allow for the possibility of the deal being null, you can use the ‘?’ operator to specify that the variable or field is nullable,

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