使用 flutter 从 firebase Firestore 获取数据

Question

I have an application where i need to get user real time location and push it into database using geoflutterfire, the code is working but i do not understand why it keeps generating multiple documents, while on the other side using the same plugin, we should use only collection reference, can any help me with this, Thank you

• Picture showing pushing data into firestore using geoflutterfire plugin ( but why it keeps generating new documents, i just want to solely update the same document )

• Push data into firebase firestore

void updateDriverLocation(){
   Fluttertoast.showToast(msg: "Called");
   geoFlutterFire = Geoflutterfire();
   if(latitude != 0.0 && longitude != 0.0){
      GeoFirePoint geoFirePoint = geoFlutterFire.point(latitude: latitude, longitude: longitude);
      var map = HashMap<String,Object>();
      map['name'] = _firebaseAuth.currentUser!.uid;
      map['position'] = geoFirePoint.data;
      _firebaseFirestore.collection("Drivers").add(map);
   }
 }

• get data from firebase firebase

   void getDrivers(){
    geoFlutterFire = Geoflutterfire();
    GeoFirePoint geoFirePoint = GeoFirePoint(latitude, longitude);
    var ref = _firebaseFirestore.collection('Drivers');
    var locations = geoFlutterFire.collection(collectionRef: ref).within(center: geoFirePoint, radius: maxRadius, field: 'position');
    locations.listen((List<DocumentSnapshot> documentList) {
       for (var documentSnapshot in documentList) {
         Map<String,Object> map = documentSnapshot.get('geopoint');
         double lat = map['latitude'] as double;
         double lon = map['longitude'] as double;
         //_list.add(LatLng(lat, lon));
         markers.add(Marker(
                    markerId: MarkerId(DateTime.now().millisecond.toString()),
                    position: LatLng(lat,lon),
                    icon: BitmapDescriptor.defaultMarker
                ));
       }
    });
  }

• This is how i'm trying to listen to the data returned from firestore

Answer 1

_firebaseFirestore.collection("Drivers").add(map);

The .add() method creates a new document with a random ID every time. If you want to update a specific document then you must use update() on a DocumentReference . Try the following:

_firebaseFirestore.collection("Drivers").doc(_firebaseAuth.currentUser!.uid).update(map);

This will update current drivers document only.

---

GeoFlutterFire has the following to specify DocID:

geoRef.setDoc(String id, var data, {bool merge})