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我正在尝试使用颤振在地图视图中显示当前用户位置。在 iOS 中，这很简单，只需添加即可self.mapView.showsUserLocation = YES;在地图视图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？

我也试图以颤振的方式实现它，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)

这是我的代码片段 -

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),
                  ],
                )),
          )
        ]),
      ),
    );
  }
}
4

2 回答 2

2

请与您的Google_maps_flutter插件一起使用插件地理定位器插件

不要忘记在你的androidmanifest.xml中添加uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"

于 2020-07-26T04:11:31.347 回答
1

关于问题：问题出在android模拟器上。在模拟器中更新谷歌播放服务应用程序然后重新启动模拟器后再次解决了我的问题。

对于简化的实现，我认为 Vasanth Vadivel 已经在这里推荐的地理定位器插件会很棒。

于 2020-07-27T03:59:36.000 回答