tlserver
commented
2 years ago Can you provide reproduction step?
Closed comatory closed 2 years ago
tlserver
commented
2 years ago Can you provide reproduction step?
comatory
commented
2 years ago @tlserver Sure
This is the toy app I created to reproduce this:
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter_map/flutter_map.dart';
import 'package:flutter_map_location_marker/flutter_map_location_marker.dart';
import 'package:latlong2/latlong.dart';
import 'package:geolocator/geolocator.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
@override
Widget build(BuildContext context) {
return const MaterialApp(
title: 'Flutter map location marker',
home: MyHomePage(),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({Key? key}) : super(key: key);
@override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
bool _locationServiceEnabled = false;
LocationPermission? _permission;
StreamSubscription<ServiceStatus>? _serviceStatusSubscription;
MapController? _controller;
@override
void initState() {
super.initState();
_getLocationPermission();
_serviceStatusSubscription =
Geolocator.getServiceStatusStream().listen(_handleServiceStatusChange);
}
@override
void dispose() {
_serviceStatusSubscription?.cancel();
super.dispose();
}
Future<bool> _getLocationPermission() async {
final locationServiceEnabled = await Geolocator.isLocationServiceEnabled();
try {
final permission = await Geolocator.requestPermission();
setState(() {
_locationServiceEnabled = locationServiceEnabled;
_permission = permission;
_logPermissionAndServiceStatus(
locationServiceEnabled: locationServiceEnabled,
permission: permission);
});
return Future.value(
locationServiceEnabled && _isLocationPermitted(permission));
} on Exception catch (_) {
const permission = LocationPermission.unableToDetermine;
setState(() {
_locationServiceEnabled = locationServiceEnabled;
_permission = permission;
_logPermissionAndServiceStatus(
locationServiceEnabled: locationServiceEnabled,
permission: permission);
});
return Future.value(false);
}
}
Future<void> _setCurrentLocationCenter(bool allowed) async {
if (!allowed) {
return;
}
final position = await Geolocator.getCurrentPosition();
final center = LatLng(position.latitude, position.longitude);
_controller?.move(center, 13.0);
}
Future<void> _handleServiceStatusChange(ServiceStatus status) async {
try {
final permission = await Geolocator.checkPermission();
final locationServiceEnabled = _isLocationServiceEnabled(status);
setState(() {
_permission = permission;
_locationServiceEnabled = locationServiceEnabled;
_logPermissionAndServiceStatus(
locationServiceEnabled: locationServiceEnabled,
permission: permission);
});
} on Exception catch (_) {
final locationServiceEnabled = _isLocationServiceEnabled(status);
const permission = LocationPermission.unableToDetermine;
setState(() {
_locationServiceEnabled = locationServiceEnabled;
_permission = permission;
_logPermissionAndServiceStatus(
locationServiceEnabled: locationServiceEnabled,
permission: permission);
});
}
}
bool _isLocationServiceEnabled(ServiceStatus status) =>
status == ServiceStatus.enabled;
bool _isLocationPermitted(LocationPermission? permission) =>
permission == LocationPermission.always ||
permission == LocationPermission.whileInUse;
void _logPermissionAndServiceStatus({
required bool locationServiceEnabled,
required LocationPermission permission,
}) {
debugPrint(
'Location service enabled? $locationServiceEnabled\tLocation permission: $permission');
}
void _handleMapCreated(MapController controller) {
_controller = controller;
_setCurrentLocationCenter(
_locationServiceEnabled && _isLocationPermitted(_permission));
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(),
body: SizedBox.expand(
child: FlutterMap(
options:
MapOptions(onMapCreated: _handleMapCreated, zoom: 13.0, plugins: [
if (_locationServiceEnabled && _isLocationPermitted(_permission))
const LocationMarkerPlugin(),
]),
children: [
TileLayerWidget(
options: TileLayerOptions(
urlTemplate: "https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png",
subdomains: ['a', 'b', 'c'],
attributionBuilder: (_) {
return const Text("© OpenStreetMap contributors");
},
)),
if (_locationServiceEnabled && _isLocationPermitted(_permission))
LocationMarkerLayerWidget(),
],
)),
);
}
}I am also attaching the video so you know how exactly I'm turning off the services. In the code you can see that I conditionally check whether I have
https://user-images.githubusercontent.com/5990424/151961354-9f0379c3-2670-4f52-8216-d12ce966ba11.mov
If no, I do not use the plugin. In theory it would work but I think since the plugin uses Geolocator.getPositionStream internally, that stream receives error first and only later is the plugin removed.
I raised the issue here that this is problematic, I think this is another issue caused by the design.
Have you had a look at https://github.com/tlserver/flutter_map_location_marker/pull/16 that I created? If the position was provided from outside (as an option), I could handle this error in my application code.
But you should still handle this internally if you wish to keep using geolocator as dependency, it should have onError handler at minimum. At the moment telemetry in my app is reporting it as uncaught error.
tlserver
commented
2 years ago Fixed. Now v2.1 provide a callback for error handling and v3 exposed the stream.
Since the plugin creates and manages its own position stream (see https://github.com/tlserver/flutter_map_location_marker/issues/15), the error cause by turning off location access is not handled.
On application level, I can decide whether to build
LocationMarkerLayerWidgetbased on my application permission or service status. However since the stream is created with the plugin, this error reaches the position stream beforeLocationMarkerLayerWidgetis removed from widget tree.There should be
onErrorhandler or at least let the user know via callback that problem occured with the ability to somehow recover from the error.Console output: