Get GPS location via a service in Android

Question

I need to monitor user's locations using a background service, and then load them and show the path to the user.

Using an activity, it was quite easy to get GPS locations, but when I got to do it via a service, I came into a problem as it seems to only work for looper threads (or something like that).

As I've searched the internet for a solution, I've found out that many people got the same problem, but I couldn't find a working solution. Some people say that you need to use prepare->loop->quit , and some say you have to use a handlerThread, but still, I can't find out how to do such things in a proper way.

Answer 1

I don't understand what exactly is the problem with implementing location listening functionality in the Service. It looks pretty similar to what you do in Activity. Just define a location listener and register for location updates. You can refer to the following code as example:

Manifest file:

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<application
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name" >
    <activity android:label="@string/app_name" android:name=".LocationCheckerActivity" >
        <intent-filter >
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <service android:name=".MyService" android:process=":my_service" />
</application>

The service file:

import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.location.Location;
import android.location.LocationManager;
import android.os.Bundle;
import android.os.IBinder;
import android.util.Log;

public class MyService extends Service {

    private static final String TAG = "BOOMBOOMTESTGPS";
    private LocationManager mLocationManager = null;
    private static final int LOCATION_INTERVAL = 1000;
    private static final float LOCATION_DISTANCE = 10f;

    private class LocationListener implements android.location.LocationListener {
        Location mLastLocation;

        public LocationListener(String provider) {
            Log.e(TAG, "LocationListener " + provider);
            mLastLocation = new Location(provider);
        }

        @Override
        public void onLocationChanged(Location location) {
            Log.e(TAG, "onLocationChanged: " + location);
            mLastLocation.set(location);
        }

        @Override
        public void onProviderDisabled(String provider) {
            Log.e(TAG, "onProviderDisabled: " + provider);
        }

        @Override
        public void onProviderEnabled(String provider) {
            Log.e(TAG, "onProviderEnabled: " + provider);
        }

        @Override
        public void onStatusChanged(String provider, int status, Bundle extras) {
            Log.e(TAG, "onStatusChanged: " + provider);
        }
    }

    LocationListener[] mLocationListeners = new LocationListener[]{
            new LocationListener(LocationManager.GPS_PROVIDER),
            new LocationListener(LocationManager.NETWORK_PROVIDER)
    };

    @Override
    public IBinder onBind(Intent arg0) {
        return null;
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.e(TAG, "onStartCommand");
        super.onStartCommand(intent, flags, startId);
        return START_STICKY;
    }

    @Override
    public void onCreate() {
        Log.e(TAG, "onCreate");
        initializeLocationManager();
        try {
            mLocationManager.requestLocationUpdates(
                    LocationManager.NETWORK_PROVIDER, LOCATION_INTERVAL, LOCATION_DISTANCE,
                    mLocationListeners[1]);
        } catch (java.lang.SecurityException ex) {
            Log.i(TAG, "fail to request location update, ignore", ex);
        } catch (IllegalArgumentException ex) {
            Log.d(TAG, "network provider does not exist, " + ex.getMessage());
        }
        try {
            mLocationManager.requestLocationUpdates(
                    LocationManager.GPS_PROVIDER, LOCATION_INTERVAL, LOCATION_DISTANCE,
                    mLocationListeners[0]);
        } catch (java.lang.SecurityException ex) {
            Log.i(TAG, "fail to request location update, ignore", ex);
        } catch (IllegalArgumentException ex) {
            Log.d(TAG, "gps provider does not exist " + ex.getMessage());
        }
    }

    @Override
    public void onDestroy() {
        Log.e(TAG, "onDestroy");
        super.onDestroy();
        if (mLocationManager != null) {
            for (int i = 0; i < mLocationListeners.length; i++) {
                try {
                    mLocationManager.removeUpdates(mLocationListeners[i]);
                } catch (Exception ex) {
                    Log.i(TAG, "fail to remove location listners, ignore", ex);
                }
            }
        }
    }

    private void initializeLocationManager() {
        Log.e(TAG, "initializeLocationManager");
        if (mLocationManager == null) {
            mLocationManager = (LocationManager) getApplicationContext().getSystemService(Context.LOCATION_SERVICE);
        }
    }
}