I am trying to get value from firebase in flutter. during that time, I am receiving _Flutter value returning from the Future<> type returning function. please help someone

I am having a code for fetching values from firebase.. the function gets a value from firebase by querying with an attribute

class FirebaseMethods {
  Future<List> findEvents(dynamic attribute, dynamic value) async {
    CollectionReference eventCollection =
        FirebaseFirestore.instance.collection('events');
    return eventCollection
        .where(attribute, isEqualTo: value)
        .get()
        .then((QuerySnapshot querySnapshot) {
      List events = [];
      querySnapshot.docs.forEach((doc) {
        events.add(doc.data());
      });
      return events;
    }).catchError((error) {
      print("Failed to retrieve events: $error");
    });
  }

  Future<List> findUsers(dynamic attribute, dynamic value) async {
    CollectionReference userCollection =
        FirebaseFirestore.instance.collection('profile');
    return userCollection
        .where(attribute, isEqualTo: value)
        .get()
        .then((QuerySnapshot querySnapshot) {
      List users = [];
      querySnapshot.docs.forEach((doc) {
        users.add(doc.data());
      });
      return users;
    }).catchError((error) {
      print("Failed to retrieve users: $error");
    });
  }
}

And I am calling the above function 'findUsers' in the following way:

dynamic database_functions = FirebaseMethods();

class RenderProfileView extends StatefulWidget {
  String email;
  RenderProfileView(this.email, {super.key});

  @override
  State<RenderProfileView> createState() => _RenderProfileViewState();
}

class _RenderProfileViewState extends State<RenderProfileView> {
  TextEditingController name_controller = TextEditingController();
  TextEditingController phone_number_controller = TextEditingController();

  late dynamic user_json = database_functions.findUser('email', widget.email);    // without late I am getting error and getting values with attribute 'email' = widget.email

  dynamic get_name() {
    print(user_json);
    return 'some_value';
  }
}

When the 'findUser' function is called, the printing message is -> Instance of '_Future' Someone please help.. if any other way to solve the issue please mention it.

CodePudding user response：

Future describes async operations in flutter. you must await all Futures results. Either by using the await keyword or .then property.

You could try adding initState to your stateful widget or go with a FutureBuilder depending on your use case.

Below is an edited version of your code.

dynamic database_functions = FirebaseMethods();

class RenderProfileView extends StatefulWidget {
  String email;
  RenderProfileView(this.email, {super.key});

  @override
  State<RenderProfileView> createState() => _RenderProfileViewState();
}

class _RenderProfileViewState extends State<RenderProfileView> {
  TextEditingController name_controller = TextEditingController();
  TextEditingController phone_number_controller = TextEditingController();

  late dynamic user_json;

  @override
  void initState() {
   super.initState();
   database_functions.findUser('email', widget.email).then((data) {
    user_json = data
   });
  }

  String get name => 'some_value';
}