如何在Flutter中在Google地图上绘制多边形，并将所有POI放在其中？

dependencies:
  flutter:
    sdk: flutter
  google_maps_flutter: ^2.0.10

import 'package:google_maps_flutter/google_maps_flutter.dart';

GoogleMap(
  initialCameraPosition: CameraPosition(
    target: LatLng(37.42796133580664, -122.085749655962),
    zoom: 14,
  ),
  onMapCreated: (GoogleMapController controller) {
    // 在地图创建后的回调中，可以进行一些初始化操作
    // 比如添加多边形和POI
    _addPolygon(controller);
    _addPOIs(controller);
  },
),

List<LatLng> polygonPoints = [
  LatLng(37.43296265331129, -122.08832357078792),
  LatLng(37.43006265331129, -122.08832357078792),
  LatLng(37.43006265331129, -122.08332357078792),
  LatLng(37.43296265331129, -122.08332357078792),
];

void _addPolygon(GoogleMapController controller) {
  controller.addPolygon(
    Polygon(
      polygonId: PolygonId('polygon'),
      points: polygonPoints,
      fillColor: Colors.blue.withOpacity(0.5),
      strokeColor: Colors.blue,
      strokeWidth: 2,
    ),
  );
}

void _addPOIs(GoogleMapController controller) {
  List<Marker> markers = [
    Marker(
      markerId: MarkerId('poi1'),
      position: LatLng(37.43196265331129, -122.08632357078792),
      infoWindow: InfoWindow(title: 'POI 1'),
    ),
    Marker(
      markerId: MarkerId('poi2'),
      position: LatLng(37.43196265331129, -122.08532357078792),
      infoWindow: InfoWindow(title: 'POI 2'),
    ),
    // 添加更多的POI
  ];

  controller.addMarkers(markers);
}