Adds MSL Altitude Support

geolocator_android/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 3.2.0
+
+- Adds support for receiving NMEA messages in position stream updates.
+- Adds support for getting altitude reported as height above MSL.
+
 ## 3.1.6
 
 * Switches to a package-internal implementation of the platform interface.

geolocator_android/android/src/main/java/com/baseflow/geolocator/GeolocatorPlugin.java

@@ -38,7 +38,7 @@ public class GeolocatorPlugin implements FlutterPlugin, ActivityAware {
         public void onServiceConnected(ComponentName name, IBinder service) {
           Log.d(TAG, "Geolocator foreground service connected");
           if (service instanceof GeolocatorLocationService.LocalBinder) {
-              initialize(((GeolocatorLocationService.LocalBinder) service).getLocationService());
+            initialize(((GeolocatorLocationService.LocalBinder) service).getLocationService());
           }
         }
 
@@ -51,6 +51,7 @@ public void onServiceDisconnected(ComponentName name) {
           }
         }
       };
+  @Nullable private NmeaStreamHandlerImpl nmeaStreamHandlerImpl;
   @Nullable private LocationServiceHandlerImpl locationServiceHandler;
 
   @SuppressWarnings("deprecation")
@@ -108,6 +109,10 @@ public void onAttachedToEngine(@NonNull FlutterPluginBinding flutterPluginBindin
     streamHandler.startListening(
         flutterPluginBinding.getApplicationContext(), flutterPluginBinding.getBinaryMessenger());
 
+    nmeaStreamHandlerImpl = new NmeaStreamHandlerImpl();
+    nmeaStreamHandlerImpl.startListening(
+        flutterPluginBinding.getApplicationContext(), flutterPluginBinding.getBinaryMessenger());
+
     locationServiceHandler = new LocationServiceHandlerImpl();
     locationServiceHandler.setContext(flutterPluginBinding.getApplicationContext());
     locationServiceHandler.startListening(
@@ -216,6 +221,10 @@ private void dispose() {
       streamHandler.setForegroundLocationService(null);
       streamHandler = null;
     }
+
+    if (nmeaStreamHandlerImpl != null) {
+      nmeaStreamHandlerImpl.stopListening();
+    }
     if (locationServiceHandler != null) {
       locationServiceHandler.setContext(null);
       locationServiceHandler.stopListening();

geolocator_android/android/src/main/java/com/baseflow/geolocator/NmeaStreamHandlerImpl.java

@@ -0,0 +1,82 @@
+package com.baseflow.geolocator;
+
+import android.content.Context;
+import android.util.Log;
+
+import androidx.annotation.Nullable;
+
+import com.baseflow.geolocator.location.NmeaClient;
+import com.baseflow.geolocator.location.NmeaMapper;
+
+import io.flutter.plugin.common.BinaryMessenger;
+import io.flutter.plugin.common.EventChannel;
+
+class NmeaStreamHandlerImpl implements EventChannel.StreamHandler {
+  private static final String TAG = "FlutterGeolocator";
+
+  @Nullable private EventChannel channel;
+  @Nullable private Context context;
+  @Nullable private NmeaClient nmeaClient;
+
+  public NmeaStreamHandlerImpl() {}
+
+  /**
+   * Registers this instance as event stream handler on the given {@code messenger}.
+   *
+   * <p>Stops any previously started and unstopped calls.
+   *
+   * <p>This should be cleaned with {@link #stopListening} once the messenger is disposed of.
+   */
+  void startListening(Context context, BinaryMessenger messenger) {
+    if (channel != null) {
+      Log.w(TAG, "Setting a event call handler before the last was disposed.");
+      stopListening();
+    }
+
+    channel = new EventChannel(messenger, "flutter.baseflow.com/geolocator_nmea_updates_android");
+    channel.setStreamHandler(this);
+    this.context = context;
+    this.nmeaClient = new NmeaClient(this.context);
+  }
+
+  /**
+   * Clears this instance from listening to method calls.
+   *
+   * <p>Does nothing if {@link #startListening} hasn't been called, or if we're already stopped.
+   */
+  void stopListening() {
+    if (channel == null) {
+      Log.d(TAG, "Tried to stop listening when no MethodChannel had been initialized.");
+      return;
+    }
+
+    disposeListeners();
+    channel.setStreamHandler(null);
+    channel = null;
+  }
+
+  @Override
+  public void onListen(Object arguments, EventChannel.EventSink events) {
+
+    if (nmeaClient == null) {
+      Log.e(TAG, "NMEA Client has not started correctly");
+      return;
+    }
+
+    nmeaClient.start();
+    nmeaClient.setCallback((message -> events.success(NmeaMapper.toHashMap(message))));
+  }
+
+  @Override
+  public void onCancel(Object arguments) {
+    disposeListeners();
+  }
+
+  private void disposeListeners() {
+    Log.e(TAG, "Geolocator position updates stopped");
+    if (nmeaClient != null) {
+      nmeaClient.setCallback(null);
+      nmeaClient.stop();
+    }
+  }
+}

geolocator_android/android/src/main/java/com/baseflow/geolocator/location/FusedLocationClient.java

@@ -7,21 +7,35 @@
 import android.location.Location;
 import android.os.Looper;
 import android.util.Log;
+
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
+
 import com.baseflow.geolocator.errors.ErrorCallback;
 import com.baseflow.geolocator.errors.ErrorCodes;
 import com.google.android.gms.common.api.ApiException;
 import com.google.android.gms.common.api.ResolvableApiException;
-import com.google.android.gms.location.*;
+import com.google.android.gms.location.FusedLocationProviderClient;
+import com.google.android.gms.location.LocationAvailability;
+import com.google.android.gms.location.LocationCallback;
+import com.google.android.gms.location.LocationRequest;
+import com.google.android.gms.location.LocationResult;
+import com.google.android.gms.location.LocationServices;
+import com.google.android.gms.location.LocationSettingsRequest;
+import com.google.android.gms.location.LocationSettingsResponse;
+import com.google.android.gms.location.LocationSettingsStates;
+import com.google.android.gms.location.LocationSettingsStatusCodes;
+import com.google.android.gms.location.SettingsClient;
+
 import java.util.Random;
 
 class FusedLocationClient implements LocationClient {
-    private static final String TAG = "FlutterGeolocator";
+  private static final String TAG = "FlutterGeolocator";
 
   private final Context context;
   private final LocationCallback locationCallback;
   private final FusedLocationProviderClient fusedLocationProviderClient;
+  private final NmeaClient nmeaClient;
   private final int activityRequestCode;
   @Nullable private final LocationOptions locationOptions;
 
@@ -33,14 +47,15 @@ public FusedLocationClient(@NonNull Context context, @Nullable LocationOptions l
     this.fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(context);
     this.locationOptions = locationOptions;
     this.activityRequestCode = generateActivityRequestCode();
+    this.nmeaClient = new NmeaClient(context);
 
     locationCallback =
         new LocationCallback() {
           @Override
           public synchronized void onLocationResult(LocationResult locationResult) {
             if (locationResult == null || positionChangedCallback == null) {
               Log.e(
-                      TAG,
+                  TAG,
                   "LocationCallback was called with empty locationResult or no positionChangedCallback was registered.");
               fusedLocationProviderClient.removeLocationUpdates(locationCallback);
               if (errorCallback != null) {
@@ -50,6 +65,7 @@ public synchronized void onLocationResult(LocationResult locationResult) {
             }
 
             Location location = locationResult.getLastLocation();
+            nmeaClient.enrichExtrasWithNmea(location);
             positionChangedCallback.onPositionChanged(location);
           }
 
@@ -65,16 +81,53 @@ public synchronized void onLocationAvailability(
         };
   }
 
+  private static LocationRequest buildLocationRequest(@Nullable LocationOptions options) {
+    LocationRequest locationRequest = new LocationRequest();
+
+    if (options != null) {
+      locationRequest.setPriority(toPriority(options.getAccuracy()));
+      locationRequest.setInterval(options.getTimeInterval());
+      locationRequest.setFastestInterval(options.getTimeInterval() / 2);
+      locationRequest.setSmallestDisplacement(options.getDistanceFilter());
+    }
+
+    return locationRequest;
+  }
+
+  private static LocationSettingsRequest buildLocationSettingsRequest(
+      LocationRequest locationRequest) {
+    LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder();
+    builder.addLocationRequest(locationRequest);
+
+    return builder.build();
+  }
+
+  private static int toPriority(LocationAccuracy locationAccuracy) {
+    switch (locationAccuracy) {
+      case lowest:
+        return LocationRequest.PRIORITY_NO_POWER;
+      case low:
+        return LocationRequest.PRIORITY_LOW_POWER;
+      case medium:
+        return LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY;
+      default:
+        return LocationRequest.PRIORITY_HIGH_ACCURACY;
+    }
+  }
+
   private synchronized int generateActivityRequestCode() {
     Random random = new Random();
     return random.nextInt(1 << 16);
   }
 
   @SuppressLint("MissingPermission")
   private void requestPositionUpdates(LocationOptions locationOptions) {
+    if (locationOptions != null && locationOptions.getUseMSLAltitude()) {
+      this.nmeaClient.start();
+    }
     LocationRequest locationRequest = buildLocationRequest(locationOptions);
     fusedLocationProviderClient.requestLocationUpdates(
-            locationRequest, locationCallback, Looper.getMainLooper());
+        locationRequest, locationCallback, Looper.getMainLooper());
   }
 
   @Override
@@ -151,9 +204,7 @@ public void startPositionUpdates(
     settingsClient
         .checkLocationSettings(settingsRequest)
         .addOnSuccessListener(
-            locationSettingsResponse ->
-                requestPositionUpdates(this.locationOptions)
-        )
+            locationSettingsResponse -> requestPositionUpdates(this.locationOptions))
         .addOnFailureListener(
             e -> {
               if (e instanceof ResolvableApiException) {
@@ -193,39 +244,6 @@ public void startPositionUpdates(
 
   public void stopPositionUpdates() {
     fusedLocationProviderClient.removeLocationUpdates(locationCallback);
-  }
-
-  private static LocationRequest buildLocationRequest(@Nullable LocationOptions options) {
-    LocationRequest locationRequest = new LocationRequest();
-
-    if (options != null) {
-      locationRequest.setPriority(toPriority(options.getAccuracy()));
-      locationRequest.setInterval(options.getTimeInterval());
-      locationRequest.setFastestInterval(options.getTimeInterval() / 2);
-      locationRequest.setSmallestDisplacement(options.getDistanceFilter());
-    }
-
-    return locationRequest;
-  }
-
-  private static LocationSettingsRequest buildLocationSettingsRequest(
-      LocationRequest locationRequest) {
-    LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder();
-    builder.addLocationRequest(locationRequest);
-
-    return builder.build();
-  }
-
-  private static int toPriority(LocationAccuracy locationAccuracy) {
-    switch (locationAccuracy) {
-      case lowest:
-        return LocationRequest.PRIORITY_NO_POWER;
-      case low:
-        return LocationRequest.PRIORITY_LOW_POWER;
-      case medium:
-        return LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY;
-      default:
-        return LocationRequest.PRIORITY_HIGH_ACCURACY;
-    }
+    this.nmeaClient.stop();
   }
 }