FlutterMap GetX

error

======== Exception caught by widgets library =======================================================
The following message was thrown building Obx(has builder, dirty, state: _ObxState#e7ef9):
      [Get] the improper use of a GetX has been detected. 
      You should only use GetX or Obx for the specific widget that will be updated.
      If you are seeing this error, you probably did not insert any observable variables into GetX/Obx 
      or insert them outside the scope that GetX considers suitable for an update 
      (example: GetX => HeavyWidget => variableObservable).
      If you need to update a parent widget and a child widget, wrap each one in an Obx/GetX.

The relevant error-causing widget was: 
  Obx Obx:file:///Users/sud/RageshAntony/flutter/get_sample/lib/app/modules/home/views/map_view.dart:17:12
When the exception was thrown, this was the stack: 
#0      RxInterface.notifyChildren (package:get/get_rx/src/rx_types/rx_core/rx_interface.dart:29:7)
#1      _ObxState.build (package:get/get_state_manager/src/rx_flutter/rx_obx_widget.dart:54:19)
#2      StatefulElement.build (package:flutter/src/widgets/framework.dart:4782:27)
#3      ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:4665:15)
#4      StatefulElement.performRebuild (package:flutter/src/widgets/framework.dart:4840:11)
#5      Element.rebuild (package:flutter/src/widgets/framework.dart:4355:5)
#6      ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:4643:5)
#7      StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:4831:11)
#8      ComponentElement.mount (package:flutter/src/widgets/framework.dart:4638:5)
...     Normal element mounting (7 frames)
#15     Element.inflateWidget (package:flutter/src/widgets/framework.dart:3673:14)
#16     MultiChildRenderObjectElement.inflateWidget (package:flutter/src/widgets/framework.dart:6333:36)
#17     MultiChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:6344:32)
...     Normal element mounting (34 frames)
#51     Element.inflateWidget (package:flutter/src/widgets/framework.dart:3673:14)
#52     MultiChildRenderObjectElement.inflateWidget (package:flutter/src/widgets/framework.dart:6333:36)
#53     MultiChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:6344:32)
...     Normal element mounting (259 frames)
#312    Element.inflateWidget (package:flutter/src/widgets/framework.dart:3673:14)
#313    MultiChildRenderObjectElement.inflateWidget (package:flutter/src/widgets/framework.dart:6333:36)
#314    MultiChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:6344:32)
...     Normal element mounting (397 frames)
#711    Element.inflateWidget (package:flutter/src/widgets/framework.dart:3673:14)
#712    Element.updateChild (package:flutter/src/widgets/framework.dart:3425:18)
#713    RenderObjectToWidgetElement._rebuild (package:flutter/src/widgets/binding.dart:1198:16)
#714    RenderObjectToWidgetElement.mount (package:flutter/src/widgets/binding.dart:1167:5)
#715    RenderObjectToWidgetAdapter.attachToRenderTree.<anonymous closure> (package:flutter/src/widgets/binding.dart:1112:18)
#716    BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2573:19)
#717    RenderObjectToWidgetAdapter.attachToRenderTree (package:flutter/src/widgets/binding.dart:1111:13)
#718    WidgetsBinding.attachRootWidget (package:flutter/src/widgets/binding.dart:944:7)
#719    WidgetsBinding.scheduleAttachRootWidget.<anonymous closure> (package:flutter/src/widgets/binding.dart:924:7)
(elided 11 frames from class _RawReceivePortImpl, class _Timer, dart:async, and dart:async-patch)
====================================================================================================

home_controller.dart

import 'dart:async';
import 'dart:convert';

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter_map/flutter_map.dart';
import 'package:get/get.dart';
import 'package:latlong2/latlong.dart';
import 'package:open_route_service/open_route_service.dart';

class HomeController extends GetxController {
  //TODO: Implement HomeController

  final count = 0.obs;
  late Timer timer;

  var startPlace = "".obs;
  final startPlaceController = TextEditingController();
  var markers = <Marker>[
    Marker(
      width: 20.0,
      height: 20.0,
      point: LatLng(9.872797, 78.17801),
      builder: (ctx) => Container(
        child: FlutterLogo(
          textColor: Colors.blue,
          key: ObjectKey(Colors.blue),
        ),
      ),
    )
  ].obs;

  RxList<LatLng> routePoints = <LatLng>[
    LatLng(51.5, -0.09),
    LatLng(53.3498, -6.2603),
    LatLng(48.8566, 2.3522),
  ].obs;

  late OpenRouteService client;

  @override
  void onInit() {
    super.onInit();
   timer =  Timer.periodic(Duration(seconds: 1), (Timer t) => increment());
  }

  @override
  void onReady() {
    super.onReady();
  }

  @override
  void onClose() {
    timer?.cancel();
  }
  void increment() => count.value++;


  void getPlace(double startLat,double startLng) async {
    final coding = await  client.geocodeReverseGet(point: ORSCoordinate(latitude: startLat, longitude: startLng));
    startPlace.value =  coding.features[0].properties["county"];
    startPlaceController.text = startPlace.value;
  }
  void getRoute(double startLat,double startLng,double endLat,double endLng) async {
     client = OpenRouteService(apiKey: '5b3ce3597851110001cf6248257dc61807394db7a9fe1700ca213cc3');

    print ("routing }");
    // Form Route between coordinates
    final List<ORSCoordinate> routeCoordinates = await client.directionsRouteCoordsGet(
        startCoordinate: ORSCoordinate(latitude: startLat, longitude: startLng),
        endCoordinate: ORSCoordinate(latitude: endLat, longitude: endLng),
        profileOverride: ORSProfile.drivingCar

    );
    print ("routing end");
    final coding = await  client.geocodeReverseGet(point: ORSCoordinate(latitude: startLat, longitude: startLng));
    startPlace.value =  coding.features[0].properties["county"];
    startPlaceController.text = startPlace.value;
    print("geocoding ${jsonEncode( coding.features[0].properties)}");
    // Print the route coordinates
    //  routeCoordinates.forEach(print);

    // Map route coordinates to a list of LatLng (requires google_maps_flutter package)
    // to be used in the Map route Polyline.
    routePoints.value = routeCoordinates
        .map((coordinate) => LatLng(coordinate.latitude, coordinate.longitude))
        .toList();
  }
}

home_view.dart

import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:flutter_map/flutter_map.dart';

import 'package:get/get.dart';
import 'package:get_sample/app/modules/home/views/map_view.dart';
import 'package:latlong2/latlong.dart';
import 'package:open_route_service/open_route_service.dart';

import '../controllers/home_controller.dart';

class HomeView extends GetView<HomeController> {
  @override
  Widget build(BuildContext context) {
    controller.getRoute(9.8753750, 78.1785170, 9.9545490, 78.1805230);
    return Scaffold(
      body: SafeArea(
        child: Stack(
          children: [
            MapView(), // throwing error
            Align(
                alignment: Alignment.topCenter,
                child: TextFormField(
                  controller: controller.startPlaceController,
                  decoration: InputDecoration(
                    labelText: 'Label text',
                    errorText: 'Error message',
                    border: OutlineInputBorder(),
                    suffixIcon: Icon(
                      Icons.error,
                    ),
                  ),
                ))
          ],
        ),
      ),
    );
  }
}

main.dart

import 'package:flutter/material.dart';

import 'package:get/get.dart';

import 'app/routes/app_pages.dart';

void main() {
  runApp(
    GetMaterialApp(
      title: "Application",
      initialRoute: AppPages.INITIAL,
      getPages: AppPages.routes,
    ),
  );
}

map_view.dart

import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:flutter_map/flutter_map.dart';

import 'package:get/get.dart';
import 'package:latlong2/latlong.dart';
import 'package:open_route_service/open_route_service.dart';

import '../controllers/home_controller.dart';

class MapView extends GetView<HomeController> {


  @override
  Widget build(BuildContext context) {
    return Obx( () => FlutterMap( // throwing error 
      options:  MapOptions(
        center: LatLng(9.8753750, 78.1785170),
        zoom: 15.0,
        onLongPress: (pos,lat) {
          print ("LATLANG ${lat.toString()}");
          print ("LATLANG ${pos.global.distance}");
         controller.markers.add(Marker(
            width: 20.0,
            height: 20.0,
            point: lat,
            builder: (ctx) => Container(
              child: FlutterLogo(
                textColor: Colors.blue,
                key: ObjectKey(Colors.blue),
              ),
            ),
          ));
          controller.markers.refresh();
        }
      ),
      layers: [
        TileLayerOptions(
          urlTemplate:
          'https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png',
          subdomains: ['a', 'b', 'c'],
          // For example purposes. It is recommended to use
          // TileProvider with a caching and retry strategy, like
          // NetworkTileProvider or CachedNetworkTileProvider
          tileProvider: NonCachingNetworkTileProvider(),
        ),
        MarkerLayerOptions(markers: controller.markers), // obs variable
        PolylineLayerOptions(
          polylines: [
            Polyline(
                points: controller.routePoints, // obs variable
                strokeWidth: 4.0,
                gradientColors: [
                  Color(0xffE40203),
                  Color(0xffFEED00),
                  Color(0xff007E2D),
                ]),
          ],
        ),
      ],
    ));
  }
}