i trying to get a string/check a string for a validation in my flutter app. i've been trying to use the .where() function but they gave me this error when i did it

The argument type 'Future<QuerySnapshot<Object?>>' can't be assigned to the parameter type 'Future<DocumentSnapshot<Object?>>?'

this is the code that give me the error

 final phoneNumber = ModalRoute.of(context)!.settings.arguments as String;
 CollectionReference users = FirebaseFirestore.instance.collection('users');

 return FutureBuilder<DocumentSnapshot>(
      future: users.where("phoneNumber", isEqualTo : phoneNumber).get(),
      builder:
          (BuildContext context, AsyncSnapshot<DocumentSnapshot> snapshot) {
        if (snapshot.hasError) {
          return const Text("Something went wrong");
        }
        if (snapshot == null || !snapshot.data!.exists) {
          return const Text("data doesn't exist");
        }

        if (snapshot.hasData) {
          return const Text("data exist already");
        }

        if (snapshot.connectionState == ConnectionState.done) {
          Map<String, dynamic> data =
              snapshot.data!.data() as Map<String, dynamic>;
          return Text("Full Name: ${data['full_name']} ${data['last_name']}");
        }

        return const Text("loading");
      },
    );

been trying and searching for 3-4 hours but all the reference tell me that i need to input the unique id

that will look like this

 final docSnapshot = await Firestore.instance
    .collection("$Friseur/1/$Tag/1/$Uhrzeit")
    .document(${doc_id_here})
    .get();

    if(docSnapshot.exists) {
      setState(...)
    }
    else {
      setState(...)
    }

CodePudding user response：

Add doc function with document id after where function because future parameter accept Future<DocumentSnapshot<Object?>>?

future: users.where("phoneNumber", isEqualTo : phoneNumber).doc(documentId).get(),

CodePudding user response：

Change FutureBuilder<DocumentSnapshot> to FutureBuilder<QuerySnapshot> when you use where operation it return the QuerySnapshot.