Flutter map current location : The following NoSuchMethodError was thrown building HomeScreen(dirty, state:_HomeScreenState#fc684)

Question

I am using flutter map and geolocator package to get current location and display in map but I am getting error as below

The getter 'latitude' was called on null. Receiver: null Tried calling: latitude

I have gone through this issue but haven't helped https://github.com/johnpryan/flutter_map/issues/124

I have used it in stateful widget

  LatLng _center ;
  Position currentLocation;

  Future<Position> locateUser() async {
    return Geolocator()
        .getCurrentPosition(desiredAccuracy: LocationAccuracy.high);
  }

  getUserLocation() async {
    currentLocation = await locateUser();
    setState(() {
      _center = LatLng(currentLocation.latitude, currentLocation.longitude);
    });
    print('center $_center');
  }

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

This the widget where I am calling the getUserLocation()

  Widget build(BuildContext context){
    return Scaffold(
      appBar: AppBar(
        title: Text('Plants Watch'),
        backgroundColor: Colors.green[700],
        actions: <Widget>[
          IconButton(
            icon: Icon(Icons.exit_to_app),
            onPressed: () {
              BlocProvider.of<AuthenticationBloc>(context).dispatch(
                LoggedOut(),
              );
            },
          )
        ],
      ),
      body: Stack(
        children: <Widget>[
          new FlutterMap(
                options: new MapOptions(
                  center: new LatLng(currentLocation.latitude, currentLocation.longitude),
                  maxZoom: 13.0,
                ),
                layers: [
                  new TileLayerOptions(
          urlTemplate: "https://api.tiles.mapbox.com/v4/"
              "{id}/{z}/{x}/{y}@2x.png?access_token={accessToken}",
          additionalOptions: {
            'accessToken': '<accessToken>',
            'id': 'mapbox.streets',
          },
        ),
        new MarkerLayerOptions(
          markers: [
            new Marker(
              width: 80.0,
              height: 80.0,
              point: LatLng(currentLocation.latitude, currentLocation.longitude),
              builder: (ctx) =>
              new Container(
                child: new IconButton(
                  icon: Icon(Icons.location_on),
                  color: Colors.green[700],
                  iconSize: 45.0,
                  onPressed: (){
                  print('Marker Tapped');
                  },
                ),
              ),
            ),
          ],
        ),
       ],
     ),
     Padding(
       padding: const EdgeInsets.all(16.0),
       child: Align(
         alignment: Alignment.bottomRight,
         child: FloatingActionButton(
           backgroundColor: Colors.green[700],
           child: Icon(Icons.add),
           onPressed: () {
             Navigator.push(context, MaterialPageRoute(builder: (context)=> PostPage()));
             },
             ),
            ),
          )
        ],
      )
    );
  }
}


I just want to remove the no such method error on building app.

First you need to check for location permission and the try to fetch the location. In your case, the location is ```null``` because you don't have permission to query it. — danypata, May 16 '19 at 11:42
I have defined location permission in AndroidManifest file.Can you please tell me where should I define or check the location permission. @danypata — Mahant, May 16 '19 at 11:48
For android you have to check runtime permissions and for iOS you need to add the permissions in the info.plist file. — danypata, May 16 '19 at 11:56

score 0 · Accepted Answer · answered May 21 '19 at 07:23

Issue is in MarkerLayerOption where i am calling user current location which results in the latitude error. So make changes to LatLng in both FlutterMap function and MarkerLayerOption solves the issue.

new FlutterMap(
                options: new MapOptions(
                  center: new LatLng(12.9716, 77.5946),

                  maxZoom: 13.0,
                ),
                layers: [
                  new TileLayerOptions(
          urlTemplate: "https://api.tiles.mapbox.com/v4/"
              "{id}/{z}/{x}/{y}@2x.png?access_token={accessToken}",
          additionalOptions: {
            'accessToken': '<accessToken>',
            'id': 'mapbox.streets',
          },
        ),
        new MarkerLayerOptions(
          markers: [
            new Marker(
              width: 80.0,
              height: 80.0,
              point: LatLng(12.9716, 77.5946),

              builder: (ctx) =>
              new Container(
                child: new IconButton(
                  icon: Icon(Icons.location_on),
                  color: Colors.green[700],
                  iconSize: 45.0,
                  onPressed: (){
                  print('Marker Tapped');
                  },
                ),
              ),
            ),
          ],
        ),

Flutter map current location : The following NoSuchMethodError was thrown building HomeScreen(dirty, state:_HomeScreenState#fc684)

1 Answers1