android - 使用 'google_maps_flutter' 插件无法在 Flutter 中显示当前用户位置

Question

我正在尝试使用 flutter 在 map View 中显示当前用户位置。在iOS中，很简单，只需添加self.mapView.showsUserLocation = YES;这将在 map View 中显示当前用户位置。但是在flutter中，看起来很复杂，需要写很多代码和插件。
顺便问一下，对于 Flutter 中的这个功能，有没有像原生 iOS 这样的简单解决方案？
我也试图以 flutter 的方式实现它，为此目的使用“geolocator”和“google_maps_flutter”插件，但在运行时在日志中出现异常。

Installing build\app\outputs\apk\app.apk...
Debug service listening on ws://127.0.0.1:51924/x_FSkxlnOcY=/ws
Syncing files to device sdk gphone x86...
W/one.cliffjumpe(14833): Accessing hidden method Landroid/content/Context;->getFeatureId()Ljava/lang/String; (greylist, reflection, allowed)
E/flutter (14833): [ERROR:flutter/lib/ui/ui_dart_state.cc(157)] Unhandled Exception: PlatformException(ERROR_GEOCODING_COORDINATES, grpc failed, null)
E/flutter (14833): #0      StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:569:7)
E/flutter (14833): #1      MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:156:18)

这是我的代码 fragment -

import 'package:flutter/cupertino.dart';
import 'dart:async';
import 'package:flutter/material.dart';
import 'package:geolocator/geolocator.dart';
import 'package:google_maps_flutter/google_maps_flutter.dart';

class MapScreen extends StatefulWidget {
  @override
  _MapState createState() => _MapState();
}

class _MapState extends State<MapScreen> {
  Completer<GoogleMapController> controller1;

  static LatLng _initialPosition;
  final Set<Marker> _markers = {};
  static  LatLng _lastMapPosition = _initialPosition;

  @override
  void initState() {
    super.initState();
    _getUserLocation();
  }
  void _getUserLocation() async {
    Position position = await Geolocator().getCurrentPosition(desiredAccuracy: LocationAccuracy.high);
    List<Placemark> placemark = await Geolocator().placemarkFromCoordinates(position.latitude, position.longitude);
    setState(() {
      _initialPosition = LatLng(position.latitude, position.longitude);
      print('placemark : ${placemark[0].name}');
    });
  }


  _onMapCreated(GoogleMapController controller) {
    setState(() {
      controller1.complete(controller);
    });
  }

  MapType _currentMapType = MapType.normal;

  void _onMapTypeButtonPressed() {
    setState(() {
      _currentMapType = _currentMapType == MapType.normal
          ? MapType.satellite
          : MapType.normal;
    });
  }

  _onCameraMove(CameraPosition position) {
    _lastMapPosition = position.target;
  }

  _onAddMarkerButtonPressed() {
    setState(() {
      _markers.add(
          Marker(
              markerId: MarkerId(_lastMapPosition.toString()),
              position: _lastMapPosition,
              infoWindow: InfoWindow(
                  title: "Pizza Parlour",
                  snippet: "This is a snippet",
                  onTap: (){
                  }
              ),
              onTap: (){
              },

              icon: BitmapDescriptor.defaultMarker));
    });
  }
  Widget mapButton(Function function, Icon icon, Color color) {
    return RawMaterialButton(
      onPressed: function,
      child: icon,
      shape: new CircleBorder(),
      elevation: 2.0,
      fillColor: color,
      padding: const EdgeInsets.all(7.0),
    );
  }
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: _initialPosition == null ? Container(child: Center(child:Text('loading map..', style: TextStyle(fontFamily: 'Avenir-Medium', color: Colors.grey[400]),),),) : Container(
        child: Stack(children: <Widget>[
          GoogleMap(
            markers: _markers,

            mapType: _currentMapType,
            initialCameraPosition: CameraPosition(
              target: _initialPosition,
              zoom: 14.4746,
            ),
            onMapCreated: _onMapCreated,
            zoomGesturesEnabled: true,
            onCameraMove: _onCameraMove,
            myLocationEnabled: true,
            compassEnabled: true,
            myLocationButtonEnabled: false,

          ),
          Align(
            alignment: Alignment.topRight,
            child: Container(
                margin: EdgeInsets.fromLTRB(0.0, 50.0, 0.0, 0.0),
                child: Column(
                  children: <Widget>[
                    mapButton(_onAddMarkerButtonPressed,
                        Icon(
                            Icons.add_location
                        ), Colors.blue),
                    mapButton(
                        _onMapTypeButtonPressed,
                        Icon(
                          IconData(0xf473,
                              fontFamily: CupertinoIcons.iconFont,
                              fontPackage: CupertinoIcons.iconFontPackage),
                        ),
                        Colors.green),
                  ],
                )),
          )
        ]),
      ),
    );
  }
}

Answer 1

请使用插件geolocator Plugin连同您的 Google_maps_flutter 插入
不要忘记添加使用权限 android:name="android.permission.ACCESS_FINE_LOCATION"在您的 androidmanifest.xml