geoflutterfire_plus 0.0.31

geoflutterfire_plus enables your flutter app to store and query cloud firestore documents based on their geographic location.

example/lib/main.dart

import 'dart:async';

import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/material.dart';
import 'package:geoflutterfire_plus/geoflutterfire_plus.dart';
import 'package:google_maps_flutter/google_maps_flutter.dart';
import 'package:rxdart/rxdart.dart';

import 'add_location.dart';
import 'firebase_options.dart';
import 'set_or_delete_location.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp(options: DefaultFirebaseOptions.currentPlatform);
  runApp(const App());
}

class App extends StatelessWidget {
  const App({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      debugShowCheckedModeBanner: false,
      theme: ThemeData(
        sliderTheme: SliderThemeData(
          overlayShape: SliderComponentShape.noOverlay,
        ),
      ),
      home: const Example(),
      // See using with converter example by removing comment below:
      // home: const WithConverterExample(),
      // See adding custom queries example by removing comment below:
      // home: const AdditionalQueryExample(),
      // home: const GeoFlutterFire2Example(),
    );
  }
}

/// Tokyo Station location for demo.
const _tokyoStation = LatLng(35.681236, 139.767125);

/// Reference to the collection where the location data is stored.
/// `withConverter` is available to type-safely define [CollectionReference].
final _collectionReference = FirebaseFirestore.instance.collection('locations');

/// Geo query geoQueryCondition.
class _GeoQueryCondition {
  _GeoQueryCondition({
    required this.radiusInKm,
    required this.cameraPosition,
  });

  final double radiusInKm;
  final CameraPosition cameraPosition;
}

class Example extends StatefulWidget {
  const Example({super.key});

  @override
  ExampleState createState() => ExampleState();
}

/// Example page using [GoogleMap].
class ExampleState extends State<Example> {
  /// [Marker]s on Google Maps.
  Set<Marker> _markers = {};

  /// [BehaviorSubject] of currently geo query radius and camera position.
  final _geoQueryCondition = BehaviorSubject<_GeoQueryCondition>.seeded(
    _GeoQueryCondition(
      radiusInKm: _initialRadiusInKm,
      cameraPosition: _initialCameraPosition,
    ),
  );

  /// [Stream] of geo query result.
  late final Stream<List<DocumentSnapshot<Map<String, dynamic>>>> _stream =
      _geoQueryCondition.switchMap(
    (geoQueryCondition) =>
        GeoCollectionReference(_collectionReference).subscribeWithin(
      center: GeoFirePoint(
        GeoPoint(
          _cameraPosition.target.latitude,
          _cameraPosition.target.longitude,
        ),
      ),
      radiusInKm: geoQueryCondition.radiusInKm,
      field: 'geo',
      geopointFrom: (data) =>
          (data['geo'] as Map<String, dynamic>)['geopoint'] as GeoPoint,
      strictMode: true,
    ),
  );

  /// Updates [_markers] by fetched geo [DocumentSnapshot]s.
  void _updateMarkersByDocumentSnapshots(
    List<DocumentSnapshot<Map<String, dynamic>>> documentSnapshots,
  ) {
    final markers = <Marker>{};
    for (final ds in documentSnapshots) {
      final id = ds.id;
      final data = ds.data();
      if (data == null) {
        continue;
      }
      final name = data['name'] as String;
      final geoPoint =
          (data['geo'] as Map<String, dynamic>)['geopoint'] as GeoPoint;
      markers.add(_createMarker(id: id, name: name, geoPoint: geoPoint));
    }
    debugPrint('📍 markers count: ${markers.length}');
    setState(() {
      _markers = markers;
    });
  }

  /// Creates a [Marker] by fetched geo location.
  Marker _createMarker({
    required String id,
    required String name,
    required GeoPoint geoPoint,
  }) =>
      Marker(
        markerId: MarkerId('(${geoPoint.latitude}, ${geoPoint.longitude})'),
        position: LatLng(geoPoint.latitude, geoPoint.longitude),
        infoWindow: InfoWindow(title: name),
        onTap: () => showDialog<void>(
          context: context,
          builder: (context) => SetOrDeleteLocationDialog(
            id: id,
            name: name,
            geoFirePoint: GeoFirePoint(
              GeoPoint(geoPoint.latitude, geoPoint.longitude),
            ),
          ),
        ),
      );

  /// Current detecting radius in kilometers.
  double get _radiusInKm => _geoQueryCondition.value.radiusInKm;

  /// Current camera position on Google Maps.
  CameraPosition get _cameraPosition => _geoQueryCondition.value.cameraPosition;

  /// Initial geo query detection radius in km.
  static const double _initialRadiusInKm = 1;

  /// Google Maps initial camera zoom level.
  static const double _initialZoom = 14;

  /// Google Maps initial target position.
  static final LatLng _initialTarget = LatLng(
    _tokyoStation.latitude,
    _tokyoStation.longitude,
  );

  /// Google Maps initial camera position.
  static final _initialCameraPosition = CameraPosition(
    target: _initialTarget,
    zoom: _initialZoom,
  );

  @override
  void dispose() {
    _geoQueryCondition.close();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Stack(
        children: [
          GoogleMap(
            zoomControlsEnabled: false,
            myLocationButtonEnabled: false,
            initialCameraPosition: _initialCameraPosition,
            onMapCreated: (_) =>
                _stream.listen(_updateMarkersByDocumentSnapshots),
            markers: _markers,
            circles: {
              Circle(
                circleId: const CircleId('value'),
                center: LatLng(
                  _cameraPosition.target.latitude,
                  _cameraPosition.target.longitude,
                ),
                // multiple 1000 to convert from kilometers to meters.
                radius: _radiusInKm * 1000,
                fillColor: Colors.black12,
                strokeWidth: 0,
              ),
            },
            onCameraMove: (cameraPosition) {
              debugPrint('📷 lat: ${cameraPosition.target.latitude}, '
                  'lng: ${cameraPosition.target.latitude}');
              _geoQueryCondition.add(
                _GeoQueryCondition(
                  radiusInKm: _radiusInKm,
                  cameraPosition: cameraPosition,
                ),
              );
            },
            onLongPress: (latLng) => showDialog<void>(
              context: context,
              builder: (context) => AddLocationDialog(latLng: latLng),
            ),
          ),
          Container(
            width: double.infinity,
            margin: const EdgeInsets.only(top: 64, left: 16, right: 16),
            padding: const EdgeInsets.all(16),
            decoration: const BoxDecoration(
              color: Colors.black38,
              borderRadius: BorderRadius.all(Radius.circular(8)),
            ),
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              crossAxisAlignment: CrossAxisAlignment.start,
              mainAxisSize: MainAxisSize.min,
              children: [
                const Text(
                  'Debug window',
                  style: TextStyle(
                    color: Colors.white,
                    fontWeight: FontWeight.bold,
                  ),
                ),
                const SizedBox(height: 8),
                Text(
                  'Currently detected count: '
                  '${_markers.length}',
                  style: const TextStyle(color: Colors.white),
                ),
                const SizedBox(height: 8),
                Text(
                  'Current radius: '
                  '${_radiusInKm.toStringAsFixed(1)} (km)',
                  style: const TextStyle(color: Colors.white),
                ),
                const SizedBox(height: 8),
                Slider(
                  value: _radiusInKm,
                  min: 1,
                  max: 100,
                  divisions: 99,
                  label: _radiusInKm.toStringAsFixed(1),
                  onChanged: (value) => _geoQueryCondition.add(
                    _GeoQueryCondition(
                      radiusInKm: value,
                      cameraPosition: _cameraPosition,
                    ),
                  ),
                ),
              ],
            ),
          ),
        ],
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: () => showDialog<void>(
          context: context,
          builder: (context) => const AddLocationDialog(),
        ),
        child: const Icon(Icons.add),
      ),
    );
  }
}