flutter_polyline_point

问题描述

这里是flutter_polyline_point

的Flutter文档中给出的例子

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

import 'Constants.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Polyline example',theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then,without quitting the app,try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",// or simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.orange,),home: MapScreen(),);
  }
}

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

class _MapScreenState extends State<MapScreen> {
  GoogleMapController mapController;
  double _originLatitude = 6.5212402,_originLongitude = 3.3679965;
  double _destLatitude = 6.849660,_destLongitude = 3.648190;
  Map<MarkerId,Marker> markers = {};
  Map<PolylineId,Polyline> polylines = {};
  List<LatLng> polylineCoordinates = [];
  PolylinePoints polylinePoints = PolylinePoints();
  String googleAPiKey = Constants.MAP_API_KEY;

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

    /// origin marker
    _addMarker(LatLng(_originLatitude,_originLongitude),"origin",BitmapDescriptor.defaultMarker);

    /// destination marker
    _addMarker(LatLng(_destLatitude,_destLongitude),"destination",BitmapDescriptor.defaultMarkerWithHue(90));
    _getPolyline();
  }

  @override
  Widget build(BuildContext context) {
    return SafeArea(
      child: Scaffold(
          body: GoogleMap(
            initialCameraPosition: CameraPosition(
                target: LatLng(_originLatitude,zoom: 15),myLocationEnabled: true,tiltGesturesEnabled: true,compassEnabled: true,scrollGesturesEnabled: true,zoomGesturesEnabled: true,onMapCreated: _onMapCreated,markers: Set<Marker>.of(markers.values),polylines: Set<Polyline>.of(polylines.values),)),);
  }

  void _onMapCreated(GoogleMapController controller) async {
    mapController = controller;
  }

  _addMarker(LatLng position,String id,BitmapDescriptor descriptor) {
    MarkerId markerId = MarkerId(id);
    Marker marker =
    Marker(markerId: markerId,icon: descriptor,position: position);
    markers[markerId] = marker;
  }

  _addPolyLine() {
    PolylineId id = PolylineId("poly");
    Polyline polyline = Polyline(
        polylineId: id,color: Colors.red,points: polylineCoordinates);
    polylines[id] = polyline;
    setState(() {});
  }

  _getPolyline() async {
    PolylineResult result = await polylinePoints.getRouteBetweenCoordinates(
        Constants.API_KEY,PointLatLng(_originLatitude,PointLatLng(_destLatitude,travelMode: TravelMode.driving,wayPoints: [PolylineWayPoint(location: "Sabo,Yaba Lagos Nigeria")]
    );
    if (result.points.isNotEmpty) {
      result.points.forEach((PointLatLng point) {
        polylineCoordinates.add(LatLng(point.latitude,point.longitude));
      });
    }
    _addPolyLine();
  }
}

API_KEY 和 MAP_API_KEY 之间有什么区别？尝试执行示例时出现错误。

我的要求是获取谷歌地图中两个地方之间的折线点。 请给我一些例子来绘制折线；如果你有。我在绘制路线时遇到问题。尝试了很多例子，但没有得到它。

解决方法

要使用谷歌地图，您需要从以下链接获取 API 密钥：

https://developers.google.com/maps/documentation/javascript/get-api-key

这应该是 MAP_API_KEY 常量。

---

要使用方向 API，您需要从以下链接获取 API 密钥：

https://developers.google.com/maps/documentation/directions/get-api-key

这应该是 API_KEY 常量。