Flutter Geolocator Plugin
A Flutter geolocation plugin which provides easy access to the platform specific location services (FusedLocationProviderClient or if not available the LocationManager on Android and CLLocationManager on iOS).
Branch | Build Status |
---|---|
develop | |
master |
Features
- Get the current location of the device;
- Get the last known location;
- Get continuous location updates;
- Check if location services are enabled on the device;
- Translate an address to geocoordinates and vice verse (a.k.a. Geocoding);
- Calculate the distance (in meters) between two geocoordinates;
- Check the availability of Google Play services (on Android only).
Usage
To use this plugin, add geolocator
as a dependency in your pubspec.yaml file. For example:
dependencies:
geolocator: '^4.0.0'
NOTE: There's a known issue with integrating plugins that use Swift into a Flutter project created with the Objective-C template. See issue Flutter#16049 for help on integration.
API
Geolocation
To query the current location of the device simply make a call to the getCurrentPosition
method:
import 'package:geolocator/geolocator.dart';
Position position = await Geolocator().getCurrentPosition(desiredAccuracy: LocationAccuracy.high);
To query the last known location retrieved stored on the device you can use the getLastKnownPosition
method (note that this can result in a null
value when no location details are available):
import 'package:geolocator/geolocator.dart';
Position position = await Geolocator().getLastKnownPosition(desiredAccuracy: LocationAccuracy.high);
To listen for location changes you can subscribe to the onPositionChanged
stream. Supply an instance of the LocationOptions
class to configure
the desired accuracy and the minimum distance change (in meters) before updates are send to the application.
import 'package:geolocator/geolocator.dart';
var geolocator = Geolocator();
var locationOptions = LocationOptions(accuracy: LocationAccuracy.high, distanceFilter: 10);
StreamSubscription<Position> positionStream = geolocator.getPositionStream(locationOptions).listen(
(Position position) {
print(_position == null ? 'Unknown' : _position.latitude.toString() + ', ' + _position.longitude.toString());
});
To check if location services are enabled you can call the checkGeolocationPermissionStatus
method. This method returns a value of the GeolocationStatus
enum indicating the availability of the location services on the device. Optionally you can specify if you want to test for GeolocationPermission.locationAlways
or GeolocationPermission.locationWhenInUse
(by default GeolocationPermission.location
is used, which checks for either one of the previously mentioned permissions). Example usage:
import 'package:geolocator/geolocator.dart';
GeolocationStatus geolocationStatus = await Geolocator().checkGeolocationPermissionStatus();
By default Geolocator
will use FusedLocationProviderClient
on Android when Google Play Services are available. It will fall back to LocationManager
when it is not available. You can override the behaviour by setting forceAndroidLocationManager
.
import 'package:geolocator/geolocator.dart';
Geolocator geolocator = Geolocator()..forceAndroidLocationManager = true;
GeolocationStatus geolocationStatus = await geolocator.checkGeolocationPermissionStatus();
To check if location services are enabled(Location Service(GPS) turned on) on the device checkGeolocationPermissionStatus
will return disabled
state if location service feature is disabled (or not available) on the device.
Geocoding
To translate an address into latitude and longitude coordinates you can use the placemarkFromAddress
method:
import 'package:geolocator/geolocator.dart';
List<Placemark> placemark = await Geolocator().placemarkFromAddress("Gronausestraat 710, Enschede");
If you want to translate latitude and longitude coordinates into an address you can use the placemarkFromCoordinates
method:
import 'package:geolocator/geolocator.dart';
List<Placemark> placemark = await Geolocator().placemarkFromCoordinates(52.2165157, 6.9437819);
Both the placemarkFromAddress
and placemarkFromCoordinates
accept an optional localeIdentifier
parameter. This paramter can be used to enforce the resulting placemark to be formatted (and translated) according to the specified locale. The localeIdentifier
should be formatted using the syntax: [languageCode]_[countryCode]. Use the ISO 639-1 or ISO 639-2 standard for the language code and the 2 letter ISO 3166-1 standard for the country code. Some examples are:
Locale identifier | Description |
---|---|
en | All English speakers (will translate all attributes to English) |
en_US | English speakers in the United States of America |
en_UK | English speakers in the United Kingdom |
nl_NL | Dutch speakers in The Netherlands |
nl_BE | Dutch speakers in Belgium |
Calculate distance
To calculate the distance (in meters) between two geocoordinates you can use the distanceBetween
method. The distanceBetween
method takes four parameters:
Parameter | Type | Description |
---|---|---|
startLatitude | double | Latitude of the start position |
startLongitude | double | Longitude of the start position |
endLatitude | double | Latitude of the destination position |
endLongitude | double | Longitude of the destination position |
import 'package:geolocator/geolocator.dart';
double distanceInMeters = await Geolocator().distanceBetween(52.2165157, 6.9437819, 52.3546274, 4.8285838);
See also the example project for a complete implementation.
Permissions
Android
On Android you'll need to add either the ACCESS_COARSE_LOCATION
or the ACCESS_FINE_LOCATION
permission to your Android Manifest. Todo so open the AndroidManifest.xml file and one of the following two lines as direct children of the <manifest>
tag:
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
NOTE: Specifying the
ACCESS_COARSE_LOCATION
permission results in location updates with an accuracy approximately equivalant to a city block. More information can be found here.
iOS
On iOS you'll need to add the NSLocationWhenInUseUsageDescription
to your Info.plist file in order to access the device's location. Simply open your Info.plist file and add the following:
<key>NSLocationWhenInUseUsageDescription</key>
<string>This app needs access to location when open.</string>
If you would like to access the device's location when your App is running in the background, you should also add the NSLocationAlwaysAndWhenInUseUsageDescription
(if your App support iOS 10 or earlier you should also add the key NSLocationAlwaysUsageDescription
) key to your Info.plist file:
<key>NSLocationAlwaysUsageDescription</key>
<string>This app needs access to location when in the background.</string>
<key>NSLocationAlwaysAndWhenInUseUsageDescription</key>
<string>This app needs access to location when open and in the background.</string>
Location accuracy
The table below outlines the accuracy options per platform:
Android | iOS | |
---|---|---|
lowest | 500m | 3000m |
low | 500m | 1000m |
medium | 100 - 500m | 100m |
high | 0 - 100m | 10m |
best | 0 - 100m | ~0m |
bestForNavigation | 0 - 100m | Optimized for navigation |
Issues
Please file any issues, bugs or feature request as an issue on our GitHub page.
Want to contribute
If you would like to contribute to the plugin (e.g. by improving the documentation, solving a bug or adding a cool new feature), please carefully review our contribution guide and send us your pull request.
Author
This Geolocator plugin for Flutter is developed by Baseflow. You can contact us at hello@baseflow.com