davidguzman70 / simplelocation

Simple platform independent location manager

SimpleLocation

Simple cross-platform location manager for Xamarin (Android and iOS)

Features

• latest native location APIs accessible from shared code
• get last location
• receive location updates
• different accuracy levels (navigation, high, balanced, low)
• distance filter
• automatic error handling for location settings
• can be used in the background (f.e. in a Service on Android)
• permission handling for Android API 23+

Setup

Android

Add permission ACCESS_FINE_LOCATION to your AndroidManifest.xml:

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

Set a context for your SimpleLocationManager, f.e. in OnCreate() of your MainActivity:

SimpleLocationManager.SetContext(this);

In case the device's location settings are disabled, the user gets informed by a system dialog (only available when your context is an Activity). If the user enables location settings this way and you want to automatically get location updates, you must call HandleResolutionResultForLocationSettings in your Activity's OnActivityResult and pass the request code and result code.

protected override void OnActivityResult(int requestCode, Result resultCode, Intent data)
{
    simpleLocationManager.HandleResolutionResultForLocationSettings(requestCode, resultCode);
    ...  
}

You can configure the system dialog behavior with HowOftenShowUseLocationDialog and ShowNeverButtonOnUseLocationDialog.

Using background location: Works out of the box now. Your context no longer needs to be an Activity. You can use SimpleLocationManager in a Service now.

Handling permissions for API 23+: Since API level 23 it is necessary to request permission for accessing location. SimpleLocation can handle this for you. All you need to do is

• pass an Activity to SimpleLocationManager.SetContext(this)
• set SimpleLocationManager.HandleLocationPermission = true where you configure SimpleLocationManager
• call HandleResultForLocationPermissionRequest in your Activitys OnRequestPermissionsResult and pass the request code, permissions, and granted results

public override void OnRequestPermissionsResult(int requestCode, string[] permissions, Permission[] grantResults)
{
    simpleLocationManager.HandleResultForLocationPermissionRequest(requestCode, permissions, grantResults);
    ...
}

In case you want to show a request permission rationale, you can use the ShowRequestPermissionRationale delegate. Set SimpleLocationManager.ShouldShowRequestPermissionRationale = true where you configure SimpleLocationManager. Don’t forget to call RequestPermission on your SimpleLocationManager instance again when closing your rationale (see demo app).

iOS

Important: Currently SimpleLocation only works on iOS 8 or higher.

Add entries for NSLocationAlwaysUsageDescription and NSLocationWhenInUseUsageDescription to your Info.plist:

<key>NSLocationAlwaysUsageDescription</key>
<string>We want to use your location when the app is in background</string>
<key>NSLocationWhenInUseUsageDescription</key>
<string>We want to use your location when the app is in foreground</string>

Using background location: If your app is supposed to get location updates while it is in the background, you have to do some additional setup.

Enable background mode and add location in your Info.plist:

<key>UIBackgroundModes</key>
<array>
	<string>location</string>
</array>

Enable requesting authorization for usage in background, f.e. in your AppDelegate before starting location updates:

SimpleLocationManager.RequestAlwaysAuthorization = true;

Optionally you can let iOS pause location updates automatically by setting

SimpleLocationManager.PausesLocationUpdatesAutomatically = true;

On some devices this boolean is set to true by default, but the default value for SimpleLocationManager is false.

Usage

Create an instance of SimpleLocationManager:

var simpleLocationManager = new SimpleLocationManager();

Define what should happen when the location gets updated:

simpleLocationManager.LocationUpdated += delegate {
    Console.WriteLine(simpleLocationManager.LastLocation);
}

To start location updates call

simpleLocationManager.StartLocationUpdates(LocationAccuracy.Balanced, 5, TimeSpan.FromMinutes(1), TimeSpan.FromSeconds(30));

The TimeSpan parameters will be taken into consideration only on Android (see here for interval and here for fastestInterval). Default values are 1 hour for interval and 10 minutes for fastestInterval. On iOS just call

simpleLocationManager.StartLocationUpdates(LocationAccuracy.Balanced, 5);

Now every time the location gets successfully updated SimpleLocationManager.LastLocation gets updated and SimpleLocationManager.LocationUpdated gets called.

To stop location updates just call

simpleLocationManager.StopLocationUpdates();

Logging

SimpleLocation internally uses its own logger, a static class called SimpleLocationLogger. Its log statements appear like [SimpleLocation: some message]. You can disable logging by calling

SimpleLocationLogger.Enabled = false;