Flutter - 谷歌地图，不显示我的位置

Question

它似乎已经正确地写了所有内容，但我不明白为什么它没有在地图上显示我的位置。

为什么不显示我的位置？

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

class MyMap extends StatefulWidget {
  @override
  MyMapState createState() => MyMapState();
}

class MyMapState extends State<MyMap> {
  GoogleMapController mapController;

  final LatLng _center = const LatLng(50.006406, 36.236484);

  void _onMapCreated(GoogleMapController controller) {
    mapController = controller;
    mapController.addMarker(
      MarkerOptions(
        position: LatLng(50.006406, 36.236484),
        infoWindowText: InfoWindowText('My Location', 'Office'),
        icon: BitmapDescriptor.defaultMarker,
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text('Map'),
          backgroundColor: Colors.green[700],
        ),
        body: GoogleMap(
          onMapCreated: _onMapCreated,
          options: GoogleMapOptions(
            scrollGesturesEnabled: true,
            tiltGesturesEnabled: true,
            rotateGesturesEnabled: true,
            myLocationEnabled: true,
            compassEnabled: true,
            cameraPosition: CameraPosition(
              target: _center,
              zoom: 11.0,
            ),
          ),
        ),
      );
  }
}

Answer 1

如果您想在地图上查看您的当前位置，并启用将您带到那里的右下方FAB功能，请确保您在 GoogleMap Widget上将属性myLocationEnabled设置为true。

      [...]
      body: GoogleMap(
          myLocationEnabled: true,
          [...]
      )

Answer 2

你需要使用flutter的 location包来跟踪用户的位置，并且你需要在你的代码中加入这个函数

_getLocation() async {
    var location = new Location();
    try {
      currentLocation = await location.getLocation();

      print("locationLatitude: ${currentLocation.latitude}");
      print("locationLongitude: ${currentLocation.longitude}");
      setState(
          () {}); //rebuild the widget after getting the current location of the user
    } on Exception {
      currentLocation = null;
    }
  }

这个函数应该在你的initState()函数中调用如下

@override
  void initState() {
    _getLocation();
    super.initState();
  }

并且不要忘记将位置包导入到您的代码中，

import 'package:location/location.dart';

按照位置包的安装指南，因为您需要AndroidManifest.xml为android和info.plistiphone添加位置权限，位置包将负责在运行时向用户请求位置权限

希望它有帮助并祝你好运

Answer 3

您必须提供对当前位置 ios 的访问权限：Info.plist

    <key>NSLocationWhenInUseUsageDescription</key>
    <string>Application needs to access your current location</string>
    <key>NSLocationAlwaysUsageDescription</key>
    <string>Application needs to access your current location</string>

安卓：AndroidManifest.xml

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />