[android] Add a way to use a custom location source (#8710)

* add a way to use a custom location source

* add custom location engine example to test app

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/MapboxMap.java

@@ -37,10 +37,12 @@ import com.mapbox.mapboxsdk.constants.MyLocationTracking;
 import com.mapbox.mapboxsdk.constants.Style;
 import com.mapbox.mapboxsdk.geometry.LatLng;
 import com.mapbox.mapboxsdk.geometry.LatLngBounds;
+import com.mapbox.mapboxsdk.location.LocationSource;
 import com.mapbox.mapboxsdk.maps.widgets.MyLocationViewSettings;
 import com.mapbox.mapboxsdk.style.layers.Filter;
 import com.mapbox.mapboxsdk.style.layers.Layer;
 import com.mapbox.mapboxsdk.style.sources.Source;
+import com.mapbox.services.android.telemetry.location.LocationEngine;
 import com.mapbox.services.commons.geojson.Feature;
 
 import java.lang.reflect.ParameterizedType;
@@ -1772,6 +1774,18 @@ public final class MapboxMap {
     trackingSettings.setOnMyLocationChangeListener(listener);
   }
 
+  /**
+   * Replaces the location source of the my-location layer.
+   *
+   * @param locationSource A {@link LocationEngine} location source to use in the my-location layer.
+   *                       Set to null to use the default {@link LocationSource}
+   *                       location source.
+   */
+  @UiThread
+  public void setLocationSource(@Nullable LocationEngine locationSource) {
+    trackingSettings.setLocationSource(locationSource);
+  }
+
   /**
    * Sets a callback that's invoked when the location tracking mode changes.
    *

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/TrackingSettings.java

@@ -12,6 +12,7 @@ import com.mapbox.mapboxsdk.constants.MyBearingTracking;
 import com.mapbox.mapboxsdk.constants.MyLocationTracking;
 import com.mapbox.mapboxsdk.location.LocationSource;
 import com.mapbox.mapboxsdk.maps.widgets.MyLocationView;
+import com.mapbox.services.android.telemetry.location.LocationEngine;
 import com.mapbox.services.android.telemetry.location.LocationEngineListener;
 import com.mapbox.services.android.telemetry.permissions.PermissionsManager;
 
@@ -26,6 +27,7 @@ public final class TrackingSettings {
   private final UiSettings uiSettings;
   private final FocalPointChangeListener focalPointChangedListener;
   private final CameraZoomInvalidator zoomInvalidator;
+  private LocationEngine locationSource;
   private LocationEngineListener myLocationListener;
 
   private boolean myLocationEnabled;
@@ -45,6 +47,7 @@ public final class TrackingSettings {
   }
 
   void initialise(MapboxMapOptions options) {
+    locationSource = LocationSource.getLocationEngine(myLocationView.getContext());
     setMyLocationEnabled(options.getLocationEnabled());
   }
 
@@ -328,9 +331,9 @@ public final class TrackingSettings {
           }
         }
       };
-      LocationSource.getLocationEngine(myLocationView.getContext()).addLocationEngineListener(myLocationListener);
+      locationSource.addLocationEngineListener(myLocationListener);
     } else {
-      LocationSource.getLocationEngine(myLocationView.getContext()).removeLocationEngineListener(myLocationListener);
+      locationSource.removeLocationEngineListener(myLocationListener);
       myLocationListener = null;
     }
   }
@@ -362,6 +365,11 @@ public final class TrackingSettings {
     myLocationView.setEnabled(locationEnabled);
   }
 
+  void setLocationSource(LocationEngine locationSource) {
+    this.locationSource = locationSource;
+    myLocationView.setLocationSource(locationSource);
+  }
+
   void update() {
     if (!myLocationView.isEnabled()) {
       return;

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/maps/widgets/MyLocationView.java

@@ -58,6 +58,7 @@ public class MyLocationView extends View {
 
   private LatLng latLng;
   private Location location;
+  private LocationEngine locationSource;
   private long locationUpdateTimestamp;
   private float previousDirection;
 
@@ -320,8 +321,7 @@ public class MyLocationView extends View {
         if (location != null) {
           setCompass(location.getBearing() - bearing);
         }
-      } else if (myBearingTrackingMode == MyBearingTracking.COMPASS
-        && compassListener.isSensorAvailable()) {
+      } else if (myBearingTrackingMode == MyBearingTracking.COMPASS && compassListener.isSensorAvailable()) {
         setCompass(magneticHeading - bearing);
       }
     }
@@ -335,8 +335,7 @@ public class MyLocationView extends View {
   }
 
   public void onStart() {
-    if (myBearingTrackingMode == MyBearingTracking.COMPASS
-      && compassListener.isSensorAvailable()) {
+    if (myBearingTrackingMode == MyBearingTracking.COMPASS && compassListener.isSensorAvailable()) {
       compassListener.onResume();
     }
     if (isEnabled()) {
@@ -369,7 +368,8 @@ public class MyLocationView extends View {
     }
 
     if (userLocationListener != null) {
-      LocationSource.getLocationEngine(getContext()).removeLocationEngineListener(userLocationListener);
+      locationSource.removeLocationEngineListener(userLocationListener);
+      locationSource = null;
       userLocationListener = null;
     }
   }
@@ -419,29 +419,32 @@ public class MyLocationView extends View {
    * @param enableGps true if GPS is to be enabled, false if GPS is to be disabled
    */
   private void toggleGps(boolean enableGps) {
-    LocationEngine locationEngine = LocationSource.getLocationEngine(getContext());
+    if (locationSource == null) {
+      locationSource = LocationSource.getLocationEngine(this.getContext());
+    }
+
     if (enableGps) {
       // Set an initial location if one available
-      Location lastLocation = locationEngine.getLastLocation();
+      Location lastLocation = locationSource.getLastLocation();
 
       if (lastLocation != null) {
         setLocation(lastLocation);
       }
 
       if (userLocationListener == null) {
-        userLocationListener = new GpsLocationListener(this);
+        userLocationListener = new GpsLocationListener(this, locationSource);
       }
 
-      locationEngine.addLocationEngineListener(userLocationListener);
-      locationEngine.activate();
+      locationSource.addLocationEngineListener(userLocationListener);
+      locationSource.activate();
     } else {
       // Disable location and user dot
       location = null;
-      locationEngine.removeLocationEngineListener(userLocationListener);
-      locationEngine.deactivate();
+      locationSource.removeLocationEngineListener(userLocationListener);
+      locationSource.deactivate();
     }
 
-    locationEngine.setPriority(LocationEnginePriority.HIGH_ACCURACY);
+    locationSource.setPriority(LocationEnginePriority.HIGH_ACCURACY);
   }
 
   public Location getLocation() {
@@ -460,8 +463,7 @@ public class MyLocationView extends View {
 
   public void setMyBearingTrackingMode(@MyBearingTracking.Mode int myBearingTrackingMode) {
     this.myBearingTrackingMode = myBearingTrackingMode;
-    if (myBearingTrackingMode == MyBearingTracking.COMPASS
-      && compassListener.isSensorAvailable()) {
+    if (myBearingTrackingMode == MyBearingTracking.COMPASS && compassListener.isSensorAvailable()) {
       compassListener.onResume();
     } else {
       compassListener.onPause();
@@ -561,22 +563,28 @@ public class MyLocationView extends View {
     contentPaddingY = (padding[1] - padding[3]) / 2;
   }
 
+  public void setLocationSource(LocationEngine locationSource) {
+    this.locationSource = locationSource;
+  }
+
   private static class GpsLocationListener implements LocationEngineListener {
 
     private WeakReference<MyLocationView> userLocationView;
+    private WeakReference<LocationEngine> locationSource;
 
-    GpsLocationListener(MyLocationView myLocationView) {
+    GpsLocationListener(MyLocationView myLocationView, LocationEngine locationEngine) {
       userLocationView = new WeakReference<>(myLocationView);
+      locationSource = new WeakReference<>(locationEngine);
     }
 
     @Override
     public void onConnected() {
       MyLocationView locationView = userLocationView.get();
       if (locationView != null) {
-        LocationEngine locationSource = LocationSource.getLocationEngine(locationView.getContext());
-        Location location = locationSource.getLastLocation();
+        LocationEngine locationEngine = locationSource.get();
+        Location location = locationEngine.getLastLocation();
         locationView.setLocation(location);
-        locationSource.requestLocationUpdates();
+        locationEngine.requestLocationUpdates();
       }
     }