LateInitializationError error in flutter_map - flutter

Question

I set up flutter_map succesfully, but when I try to filter my map by "City" for example I am getting this error:
The following LateError was thrown building FutureBuilder<List<dynamic>>(dependencies: [MediaQuery],
state: _FutureBuilderState<List<dynamic>>#cb20d):
LateInitializationError: Field '_state' has already been initialized.
The relevant error-causing widget was:
FutureBuilder<List<dynamic>>
My flutter_map implementation is as follow:
late MapController mapController;
Future<List<dynamic>>? futureLocs;
Future<List<dynamic>>? futureLocsFilteredByCity;
bool? isFilterByCity;
PageController pageController = PageController();
double currentZoom = 10.0;
PanelController panelController = PanelController();
#override
void initState() {
super.initState();
mapController = MapController();
pageController = PageController(viewportFraction: 0.7, initialPage: 0);
futureLocs = getAllDogsLocation();
}
Widget build(BuildContext context) {
return Scaffold(
appBar: GenericAppBar(context,
backbutton: true,
title: 'Dogs map',
filterbutton: true, onfilterpress: () {
showDialog(
context: context,
builder: (context) {
return CitiesToFilter(
futureLocs: futureLocs,
onCityPress: (city) {
setState(() {
isFilterByCity = true;
futureLocs = getDogLocationByCity(city);
futureLocs!.then((value) {
if (value.isNotEmpty) {
var latlong = LatLng(
value[0]['latitude'], value[0]['longitude']);
widget.lat = latlong.latitude;
widget.long = latlong.longitude;
}
});
});
});
});
}),
body: FlutterMapCusto(
futureLocs: futureLocs,
mapController: mapController,
pageController: pageController,
lat: widget.lat,
long: widget.long,
panelcontroller: panelController,
),
floatingActionButtonLocation: FloatingActionButtonLocation.endFloat,
floatingActionButton: Column(
mainAxisAlignment: MainAxisAlignment.end,
children: [
FloatingActionButton(
heroTag: Text('CurrentLoc'),
onPressed: () {
setState(() {
mapController.move(
LatLng(widget.lat, widget.long), currentZoom);
});
},
tooltip: 'Current location',
child: const Icon(Icons.location_history),
),
],
));
}
}
where FlutterMapCusto widget is defined as a normal widget with FlutterMap class. I am not including it to avoid boilerplate code here since it is a basic implementation found in the package web. I think the error is coming from mapController..
On the other hand I am fetching my new data filtered by city with the function "getDogLocationByCity(city)" updating my future.
Then we have CitiesToFilter widget:
Widget build(BuildContext context) {
return AlertDialog(
title: Text('Filter'),
content: Column(
mainAxisSize: MainAxisSize.min,
children: [
Text('Filter by City'),
FloatingActionButton(onPressed: () {
showDialog(
context: context,
builder: (context) {
return AlertDialog(
title: Text('Cities:'),
content: SizedBox(
width: MediaQuery.of(context).size.width,
child: FutureBuilder(
future: widget.futureLocs,
builder: (BuildContext context,
AsyncSnapshot<List<dynamic>> snapshot) {
switch (snapshot.connectionState) {
case ConnectionState.none:
case ConnectionState.waiting:
return Text('Loading...');
case ConnectionState.active:
{
return const Center(
child: Text('Loading...'),
);
}
case ConnectionState.done:
if (snapshot.hasError) {
return Text(
'Error: ${snapshot.error}');
}
if (snapshot.hasData) {
return ListView.builder(
itemCount:
snapshot.data!.length,
itemBuilder: (context, index) {
return TextButton(
onPressed: () {
setState(() {
widget.onCityPress( snapshot.data![index]['CityName'] );
});
Navigator.pop(context);
},
child: Text(
snapshot.data![index]
['CityName']));
});
} else {
return const Text(
'No data available');
}
}
},
),
),
);
});
})
],
),
actions: [
TextButton(
onPressed: () {
Navigator.pop(context);
},
child: Text('Close'))
],
);
}
Future method to fetch the data shown in map. This is just a wrapper developed from Back4App to interact with its MongoDb database:
Future<List<dynamic>> getAllDogsLocation() async {
await Future.delayed(const Duration(seconds: 2), () {});
QueryBuilder<ParseObject> queryTodo =
QueryBuilder<ParseObject>(ParseObject('Todo'));
// queryTodo.includeObject(['latitude']);
final ParseResponse apiResponse = await queryTodo.query();
if (apiResponse.success && apiResponse.results != null) {
return apiResponse.results as List<ParseObject>;
} else {
throw Exception('Failed to load data');
}
}