I'm trying to get a specific field called "specie" from a document in a Firebase collection. I am trying as follows but I have an error of type 'Future ' is not a subtype of type 'String' . What am I doing wrong?
Repository method:
getSpecie(String petId) {
Future<DocumentSnapshot> snapshot = petCollection.document(petId).get();
return snapshot.then((value) => Pet.fromSnapshot(value).specie);
}
Entity method:
factory Pet.fromSnapshot(DocumentSnapshot snapshot) {
Pet newPet = Pet.fromJson(snapshot.data);
newPet.reference = snapshot.reference;
return newPet;
}
factory Pet.fromJson(Map<String, dynamic> json) => _PetFromJson(json);
Pet _PetFromJson(Map<String, dynamic> json) {
return Pet(json['name'] as String,
specie: json['specie'] as String);
}
I found a solution. No needed fromJson() method, I only changed the repository method:
Future<String> getSpecie(String petId) async {
DocumentReference documentReference = petCollection.document(petId);
String specie;
await documentReference.get().then((snapshot) {
specie = snapshot.data['specie'].toString();
});
return specie;
}
Try this..
getSpecie(String petId) async{
Future<DocumentSnapshot> snapshot = await petCollection.document(petId).get();
return snapshot.then((value) => Pet.fromSnapshot(value).specie);
}
This is how I learned to get documents from firestore https://medium.com/@yasassandeepa007/how-to-get-sub-collection-data-from-firebase-with-flutter-fe1bda8456ca
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