How to add markers from the firestore in the google maps?

Question

I have tried to build a code from the internet which should draw two markers in goole maps. The difficulty is that the coordinates come from a cloud firestore. I don't know why, but I can`t see the markers. I did it the same way the people in the tutorial told me.

This is a screenshot of my firestore:

And this is the code I tried:

import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter/material.dart';
import 'package:google_maps_flutter/google_maps_flutter.dart';

class maps2 extends StatefulWidget {
  @override
  _maps2State createState() => _maps2State();
}

class _maps2State extends State<maps2> {
  GoogleMapController controller;

  Map<MarkerId, Marker> markers = <MarkerId, Marker>{};

  void initMarker(specify, specifyId) async {
    var markerIdVal = specifyId;
    final MarkerId markerId = MarkerId(markerIdVal);
    final Marker marker = Marker(
      markerId: markerId,
      position:
          LatLng(specify['location'].latitude, specify['location'].longitude),
      infoWindow: InfoWindow(title: 'Shop', snippet: specify['name']),
    );
    setState(() {
      markers[markerId] = marker;
    });
  }

  getMarkerData() async {
    Firestore.instance.collection('data').getDocuments().then((myMockDoc) {
      if (myMockDoc.documents.isNotEmpty) {
        for (int i = 0; i < myMockDoc.documents.length; i++) {
          initMarker(
              myMockDoc.documents[i].data, myMockDoc.documents[i].documentID);
        }
      }
    });
  }

  @override
  void initState() {
    getMarkerData();
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    Set<Marker> getMarker() {
      return <Marker>[
        Marker(
            markerId: MarkerId('Shop'),
            position: LatLng(21.1458, 79.0882),
            icon: BitmapDescriptor.defaultMarker,
            infoWindow: InfoWindow(title: 'Home'))
      ].toSet();
    }

    return Scaffold(
      body: GoogleMap(
        markers: Set<Marker>.of(markers.values),
        mapType: MapType.normal,
        initialCameraPosition:
            CameraPosition(target: LatLng(21.1458, 79.0882), zoom: 12.0),
        onMapCreated: (GoogleMapController controller) {
          controller = controller;
        },
      ),
    );
  }
}

Answer 1

You need to change the code to:

 initMarker(
         myMockDoc.documents[i].data(), myMockDoc.documents[i].documentID);
        }