Harry Tormey

One of the killer features of Android smartphones is the ability for applications to grab your location and provide tailored service based on it. Implementing such location services on the Android platform is pretty easy but doing it in such a way so as to not unnecessarily drain your battery can be a little tricky. I just added a location utility called GeoUtil which does just this to my crossfit workout tracking application. The following is an explanation of this utility and how to integrate it into your Android activity and if you so wish add location information to your notes using the Snaptic API.

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//Add the following member variables to your activity class
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private LocationManager mLocationManager;
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private GeoUtil mGeoUtil;
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private static final int LOCATION_UPDATE_INTERVAL_MILLIS = 5000;
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private static final float LOCATION_UPDATE_DISTANCE_METERS = 10;
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private Location externalLocation = null;
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//Add the following code to your activity onPause, onResume, onCreate
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 @Override
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 protected void onPause() {
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    mLocationManager.removeUpdates(mGeoUtil);
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    super.onPause();
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}
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@Override
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protected void onResume() {
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   super.onResume();
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   if (externalLocation == null) {
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      // Register for location updates
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      mLocationManager.requestLocationUpdates(
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         LocationManager.NETWORK_PROVIDER,
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 	 LOCATION_UPDATE_INTERVAL_MILLIS,
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 	 LOCATION_UPDATE_DISTANCE_METERS, mGeoUtil);
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 	 mLocationManager.requestLocationUpdates(
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 	 LocationManager.GPS_PROVIDER,
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 	 LOCATION_UPDATE_INTERVAL_MILLIS,
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 	 LOCATION_UPDATE_DISTANCE_METERS, mGeoUtil);
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   } else {
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 	mLocationManager.removeUpdates(mGeoUtil);
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    }
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}
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@Override
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protected void onCreate(Bundle savedInstanceState) {
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   mLocationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
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   mGeoUtil = new GeoUtil(getApplicationContext());
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}
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//Now when you want to add location information to a note do the following
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 if(mGeoUtil.hasLocation()) {//Create a note
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   SnapticNote note = new SnapticNote();
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   Location location = new Location(mGeoUtil.getLocation());
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   note.latitude =location.getLatitude();
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   note.longitude = location.getLongitude();
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   note.text = "Post note with location information";
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   int returnCode  = mApi.addNote(note);
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   if(DEBUG)Log.d(LOGCATNAME, "Print out note lat: " + note.latitude+ " note long: " +  note.longitude );
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  } else {
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     if(DEBUG)Log.d(LOGCATNAME, "No location available"); 	
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     Toast.makeText(getApplicationContext(),
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     "No location available",
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      Toast.LENGTH_LONG).show();
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}
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//Also make sure you have the following permissions in your applications manifest
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android.permission.INTERNET
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android.permission.ACCESS_FINE_LOCATION
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android.permission.ACCESS_COARSE_LOCATION
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Lets review whats going on in the above code and talk about what GeoUtil actually does. mLocationManager is the system LocationManager service. Our GeoUtil class is the update-handler class for location updates sent out by the LocationManager service, it is a sub class of LocationListener. We indicate that we want location updates and designate that these updates shall be handled by mGeoUtil. The requestLocationUpdates() call to the LocationManager service dicates how often we will get updates on the location (those parameters have direct impact on battery drain, so they've been picked for a reasonable use-case tradeoff). In the above example we ask for updates no closer than 5 seconds apart (they can come longer apart, if the system decides to) and we also put a 10m change radius on the updates, anything less than that will be filtered out and no messages sent.

I just added a function to search for a given string in your snaptic.com notes to our android-lib. This function returns a list of all notes containing that given string. In the following example I search for all notes containing the workout tag.

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ArrayList<SnapticNote> notes = new ArrayList<SnapticNote>();
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int getNotesReturnCode 	= mApi.searchNotes("#Workout", notes);
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//Only proceed if notes were fetched
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if(getNotesReturnCode == SnapticAPI.RESULT_OK){
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   //Search for notes containing descriptions of exercises
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        for(SnapticNote n : notes){
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	       if(DEBUG)Log.d(LOGCATNAME, "Note: " + n.summary);
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	}
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}
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