I am trying to build an app using flutter map plugin. But I got this error -
Before this error I added this line -
Stream<List<DocumentSnapshot>> getDataCollectionByLocation({
required GeoFirePoint center,
required double radius,
required String field,
}) {
Stream<List<DocumentSnapshot>> stream = _geo
.collection(collectionRef: ref)
.within(center: center, radius: radius, field: field);
return stream;
}
Related
I query my database for items within a distance from the user's position as follows:
/// Get a stream of nearby ads.
static Stream<List<DocumentSnapshot<Map<String, dynamic>>>> getNearbyStream(
{required Position center, required double radius}) {
final geo = Geoflutterfire();
final collectionReference =
FirebaseFirestore.instance.collection(collectionName);
final gfpCenter = GeoFirePoint(center.latitude, center.longitude);
return geo
.collection(collectionRef: collectionReference)
.within(
center: gfpCenter,
radius: radius,
field: 'position',
strictMode: true);
}
To my surprise, the results shows duplicates: each result is shown twice.
How it comes?
I made a Google map using flutter and drew two polyline on the map. I want to check if the current location is on the polyline or not.
first i need to check if my current location is on the same
this code is for how i get polyline and list of polyline coordinates
i have current location LatLng and list of polyline LatLng
polyline
import 'package:flutter/foundation.dart';
import 'package:flutter_polyline_points/flutter_polyline_points.dart';
import 'package:google_maps_flutter/google_maps_flutter.dart';
class Directions {
final LatLngBounds bounds;
final List<PointLatLng> polylinePoints;
final String polylinePointsString;
final String totalDistance;
final String totalDuration;
final String alternativeTotalDistance;
final String alternativeTotalDuration;
final List<PointLatLng> alternativePolylinePoints;
final String alternativePolylinePointsString;
const Directions(
{#required this.polylinePointsString,
#required this.alternativePolylinePointsString,
#required this.alternativePolylinePoints,
#required this.alternativeTotalDistance,
#required this.alternativeTotalDuration,
#required this.bounds,
#required this.polylinePoints,
#required this.totalDistance,
#required this.totalDuration});
factory Directions.fromMap(Map<String, dynamic> map) {
//check route is not available
if ((map['routes'] as List).isEmpty) return null;
final data = Map<String, dynamic>.from(map['routes'][0]);
final routeList = map['routes'] as List;
//bounds
final northeast = data['bounds']['northeast'];
final southwest = data['bounds']['southwest'];
final bounds = LatLngBounds(
southwest: LatLng(southwest['lat'], southwest['lng']),
northeast: LatLng(northeast['lat'], northeast['lng']));
//distance & duration
String distance = '';
String duration = '';
if ((data['legs'] as List).isNotEmpty) {
final leg = data['legs'][0];
distance = leg['distance']['text'];
duration = leg['duration']['text'];
}
// Map for allternative route
List<PointLatLng> alternativeRoutePolyLinePoints;
String alternativePolylinePointsString;
String alternativeDistance;
String alternativeDuration;
// If alternative is available
if ((map['routes'] as List).length > 1) {
final alternativeRoute = Map<String, dynamic>.from(map['routes'][1]);
alternativeRoutePolyLinePoints = PolylinePoints()
.decodePolyline(alternativeRoute['overview_polyline']['points']);
alternativePolylinePointsString =
alternativeRoute['overview_polyline']['points'];
alternativeDuration = alternativeRoute['legs'][0]['duration']['text'];
alternativeDistance = alternativeRoute['legs'][0]['distance']['text'];
} else {
alternativeRoutePolyLinePoints = null;
alternativeDuration = null;
alternativeDuration = null;
}
return Directions(
alternativePolylinePoints: alternativeRoutePolyLinePoints,
alternativeTotalDistance: alternativeDistance,
alternativeTotalDuration: alternativeDuration,
bounds: bounds,
polylinePointsString: data['overview_polyline']['points'],
alternativePolylinePointsString: alternativePolylinePointsString,
polylinePoints: PolylinePoints()
.decodePolyline(data['overview_polyline']['points']),
totalDistance: distance,
totalDuration: duration);
}
//get route information
}
import 'dart:developer';
import 'package:dio/dio.dart';
import 'package:flutter/cupertino.dart';
import 'package:google_maps_flutter/google_maps_flutter.dart';
import '../model/directions_model.dart';
class DirectionsRepository {
static const String _baseUrl =
'https://maps.googleapis.com/maps/api/directions/json?';
final Dio _dio;
DirectionsRepository({Dio dio}) : _dio = dio ?? Dio();
Future<Directions> getDirections({
#required bool alternative,
#required LatLng origin,
#required LatLng destination,
#required String mode,
}) async {
final response = await _dio.get(_baseUrl, queryParameters: {
'origin': '${origin.latitude},${origin.longitude}',
'destination': '${destination.latitude},${destination.longitude}',
'mode': '$mode',
// 'waypoints':'${waypoints}',
'alternatives': alternative ? 'true' : 'false',
'key': "google api key",
});
if (response.statusCode == 200) {
log(response.data.toString());
return Directions.fromMap(response.data);
}
return null;
}
}
Somehow, I can't get this code to work:
My model is this:
class Location {
final String name;
final String route;
final String id;
final GeoPoint location;
final List images;
final String address;
Location(
{this.name,
this.route,
this.id,
this.location,
this.images,
this.address});
}
Here's the Firebase snapshot that works just fine without the location field.
List<Location> _locationListFromSnapshot(QuerySnapshot snapshot) {
return snapshot.docs.map((doc) {
return Location(
name: doc["name"]["ru"] ?? '',
route: doc["route"] ?? '',
address: doc["address"]["ru"] ?? '',
images: doc["images"],
id: doc['id'] ?? '',
location: doc["location"]);
}).toList();
}
Here's the error thrown:
Unhandled Exception: Bad state: field does not exist within the DocumentSnapshotPlatform
Since the code works fine without the location field, then it means that the location field does not exist in the document.
I'm able to find locations within firestore documents if those have the next structure:
But how to perform the same searching, if the JSON has a couple of geopoints? Like this:
I'm using geoflutterfire with cloud_firestore.
The code to save locations to the database:
final geo = Geoflutterfire();
final startPoint = geo.point(
latitude: 49.805378,
longitude: 23.982382,
);
final finishPoint = geo.point(
latitude: 49.79987621408566,
longitude: 24.035205183081246,
);
FirebaseFirestore.instance.collection('Drivers').doc('12345').set({
'location': [startPoint.data, finishPoint.data]
});
This code is for getting filtered locations:
final drivers = FirebaseFirestore.instance.collection('Drivers');
final geo = Geoflutterfire();
final center = geo.point(
latitude: 49.79987621408566,
longitude: 24.035205183081246,
);
final Stream<List<DocumentSnapshot>> stream =
geo.collection(collectionRef: drivers).within(
center: center,
radius: 4,
field: 'location',
strictMode: true,
);
stream.listen((List<DocumentSnapshot> documentList) {
// Always empty if there are arrays of locations.
print(documentList);
});
How can I store firebase data so that I can use it for markers on a googlemap?
late CollectionReference vendorLocCollection =
FirebaseFirestore.instance.collection('vendorlocations');
late List vendors = [];
Future <void> populateVendors() async {
Map<dynamic, dynamic> marker = <MarkerId, Marker> {}; //from dynamic in snapshot to marker
final _vendorSnapshots = await vendorLocCollection.snapshots();
_vendorSnapshots.listen((result) {
result.docs.forEach((result) { //how do i extract the result so i can use
// it as marker? :
vendors.add(result.data());
print(vendors);
});
});
}
Parsing firebase snapshot results and putting markers on Google Maps are two different things.
Step 1: Serialise the data
Since we get the data in JSON format, we first change it to dart data types.
We can use something like this.
class VendorLocations {
String uid;
double latitude;
double longitude;
VendorLocations(this.uid, this.latitude, this.longitude);
}
...
vendors = (result.data() as List)
.map((e) {
return VendorLocations(e['uid'], e['latitude'], e['longitude']);
})
.toList();
Step 2: Put marker on Google Map
Create marker objects from the vendors list.
final markerId = vendors[0].uid; /// or something else
final Marker m = Marker(
markerId: markerId,
position: LatLng(
vendors[0].latitude,
vendors[0].longitude,
),
/// specify other parameters as needed
);
marker[markerId] = m;
// update UI
This creates a new marker. All the markers can be added by running the above code snippet in a loop.
Reference : google_maps_flutter