(Flutter) Error: The argument type 'String?' can't be assigned to the parameter type 'String' because 'String?' is nullable and 'String' isn't

Question

im using flutter in android studio. coding as below.

class _loginscreenState extends State<loginscreen> {
  GlobalKey<FormState> formKey = GlobalKey<FormState>();

  String? _email, _password;

  void signin() async {
    await FirebaseAuth.instance
        .signInWithEmailAndPassword(email: _email, password: _password)
        .catchError((onError) {
      print(onError);
    }).then((authUser) => {print(authUser.user?.uid)});
  }

please help me to solve this why the code cant run and what is the meaning of "'String?' is nullable and 'String' isn't". and what is the solution?

Solution

void signin() async { 
   await FirebaseAuth.instance .signInWithEmailAndPassword(
      email: _email! /* <-- */, 
      password: _password! /* <-- */).catchError((onError) {
        print(onError);
      }).then((authUser) => print(authUser.user?.uid));
}

try to add null(!)

Comments

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