RNAndroidLocationHelperModule.java

package id.xyz.libraries;

import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.bridge.ReactContextBaseJavaModule;
import com.facebook.react.bridge.ReactMethod;
import com.facebook.react.bridge.Callback;

import android.Manifest;
import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Intent;
import android.content.IntentSender;
import android.content.pm.PackageManager;
import android.location.Location;
import android.os.Build;
import android.os.Bundle;
import android.provider.Settings;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.content.ContextCompat;
import android.text.TextUtils;
import android.util.Log;

import com.facebook.react.bridge.Promise;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.PendingResult;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Status;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.location.LocationSettingsRequest;
import com.google.android.gms.location.LocationSettingsResult;
import com.google.android.gms.location.LocationSettingsStates;
import com.google.android.gms.location.LocationSettingsStatusCodes;

import com.facebook.react.bridge.WritableMap;
import com.facebook.react.bridge.Arguments;
import com.facebook.react.bridge.ReadableMap;
import com.facebook.react.modules.core.DeviceEventManagerModule;
import android.location.Criteria;
import android.location.LocationManager;
import android.location.Location;
import java.util.List;
import android.content.Context;


public class RNAndroidLocationHelperModule extends ReactContextBaseJavaModule implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener {

  private final ReactApplicationContext reactContext;

  public RNAndroidLocationHelperModule(ReactApplicationContext reactContext) {
    super(reactContext);
    this.reactContext = reactContext;
  }

  public GoogleApiClient googleApiClient;

  @Override
  public String getName() {
    return "RNAndroidLocationHelper";
  }

  // getCurrentPosition()
  @ReactMethod
  public void getCurrentPosition(Callback successCallback, Callback errorCallback){
    Location l = RNAndroidLocationListener.getBestLastKnownPosition(this.getReactApplicationContext());
    if (l == null){
      errorCallback.invoke("Failed to retrieve current location");
      return;
    }
    successCallback.invoke(locationToMap(l));
  }
  
  private static WritableMap locationToMap(Location location) {
    WritableMap map = Arguments.createMap();
    WritableMap coords = Arguments.createMap();
    coords.putDouble("latitude", location.getLatitude());
    coords.putDouble("longitude", location.getLongitude());
    coords.putDouble("altitude", location.getAltitude());
    coords.putDouble("accuracy", location.getAccuracy());
    coords.putDouble("heading", location.getBearing());
    coords.putDouble("speed", location.getSpeed());
    map.putMap("coords", coords);
    map.putDouble("timestamp", location.getTime());
    map.putString("provider", location.getProvider());

    if (android.os.Build.VERSION.SDK_INT >= 18) {
      map.putBoolean("mocked", location.isFromMockProvider());
    }

    return map;
  }

  private static class LocationOptions {
    private final long timeout;
    private final double maximumAge;
    private final boolean highAccuracy;
    private final float distanceFilter;

    private LocationOptions(
          long timeout,
          double maximumAge,
          boolean highAccuracy,
          float distanceFilter) {
      this.timeout = timeout;
      this.maximumAge = maximumAge;
      this.highAccuracy = highAccuracy;
      this.distanceFilter = distanceFilter;
    }

    private static LocationOptions fromReactMap(ReadableMap map) {
      // precision might be dropped on timeout (double -> int conversion), but that's OK
      long timeout =
              map.hasKey("timeout") ? (long) map.getDouble("timeout") : Long.MAX_VALUE;
      double maximumAge =
              map.hasKey("maximumAge") ? map.getDouble("maximumAge") : Double.POSITIVE_INFINITY;
      boolean highAccuracy =
              map.hasKey("enableHighAccuracy") && map.getBoolean("enableHighAccuracy");
      float distanceFilter = map.hasKey("distanceFilter") ?
              (float) map.getDouble("distanceFilter") :
              10;

      return new LocationOptions(timeout, maximumAge, highAccuracy, distanceFilter);
    }
  }

  @ReactMethod
  public void watchPosition(ReadableMap options, Callback successCallback, Callback errorCallback){
      LocationOptions opts = LocationOptions.fromReactMap(options);
      LocationManager locationManager = (LocationManager)this.getReactApplicationContext().getSystemService(Context.LOCATION_SERVICE);
      Criteria criteria = new Criteria();
      if (opts.highAccuracy) {
          criteria.setAccuracy(Criteria.ACCURACY_FINE);
      }
      String bestProvider = locationManager.getBestProvider(criteria, true);

      locationManager.requestLocationUpdates(bestProvider, 1000, opts.distanceFilter, this);
  }

  @Override
  public void onLocationChanged(Location location) {
      if (location == null) return;

      this.getReactApplicationContext()
              .getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
              .emit("locationChanged", locationToMap(location));
  }
}

RNAndroidLocationListener.java

package id.xyz.libraries;

import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.bridge.ReactContextBaseJavaModule;
import com.facebook.react.bridge.ReactMethod;
import com.facebook.react.bridge.Callback;

import android.Manifest;
import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Intent;
import android.content.IntentSender;
import android.content.pm.PackageManager;
import android.location.Location;
import android.os.Build;
import android.os.Bundle;
import android.provider.Settings;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.content.ContextCompat;
import android.text.TextUtils;
import android.util.Log;

import com.facebook.react.bridge.Promise;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.PendingResult;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Status;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.location.LocationSettingsRequest;
import com.google.android.gms.location.LocationSettingsResult;
import com.google.android.gms.location.LocationSettingsStates;
import com.google.android.gms.location.LocationSettingsStatusCodes;

import com.facebook.react.bridge.WritableMap;
import com.facebook.react.bridge.Arguments;
import com.facebook.react.bridge.ReadableMap;
import com.facebook.react.modules.core.DeviceEventManagerModule;
import android.location.Criteria;
import android.location.LocationManager;
import android.location.Location;
import java.util.List;
import android.content.Context;
import android.location.LocationListener;


public class RNAndroidLocationListener implements LocationListener {

  // private final ReactApplicationContext reactContext;

  // public RNAndroidLocationHelperModule(ReactApplicationContext reactContext) {
  //   super(reactContext);
  //   this.reactContext = reactContext;
  // }

  // getCurrentPosition()
  public Location getBestLastKnownPosition(Context context) {
    LocationManager locationManager = (LocationManager)context.getSystemService(Context.LOCATION_SERVICE);
    List<String> providers = locationManager.getProviders(true);
    Location bestLocation = null;
    for (String provider : providers) {
      Location l = locationManager.getLastKnownLocation(provider);
      if (l == null) {
        continue;
      }
      if (bestLocation == null || l.getAccuracy() < bestLocation.getAccuracy()) {
        // Found best last known location: %s", l);
        bestLocation = l;
      }
    }

    if (bestLocation == null) {
      locationManager.requestSingleUpdate(new Criteria(), this, null);
    }
    return bestLocation;
  }
}