Develop Reference

How to get device location

So, I'm trying to build a weather app for practice and I've been running into the problem of trying to get the location. I've read people suggest to use getLastLocation through the fused location API, problem with that is if they don't already have a location registered on the device it comes up null. I've noticed using the emulator times that this come up is rare, but I'd still like my app to handle it properly. One instance where you might run into this is if they just turned GPS off and back on, or if the phone was just turned on. One thing I did was if getLastLocation does come back null, is to request an update, but then you still have to wait for the device to register an updated location, which with a weather app all of the data is based off of and you're still kind of running into the same problem. I've noticed with other apps this isn't a problem, like sometimes I actually have to load up Google Maps to get it to register a location. How does Google Maps force it to update the location? Here's the example from my getLocation method:
public void getLocation() throws SecurityException {
boolean gps_enabled;
LocationManager lm = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
gps_enabled = lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
if (gps_enabled) {
Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if (location != null) {
startGetForecast(location);
} else {
LocationRequest request = LocationRequest.create();
request.setNumUpdates(1);
request.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, request, this);
}
}
else {
AlertDialogFragment alertDialogFragment = new AlertDialogFragment();
alertDialogFragment.setErrorTexts("Location Unavailable", "Could not retrieve location information.", "Exit");
alertDialogFragment.show(getSupportFragmentManager(), "Location Unavailable");
}
}

Note: This answer could sound like not answering to the question directly but after chatting (comments in question) with OP as his code was ok in general but the condition around the problem, this answer has satisfied OP.
Fortunately, the standard library Is not the only way Google can get
code into your hands. In addition to the standard library, Google
provider Play services. This is a set of common services that are
installed alongside the Google Play store application. To fix this
location mess, Google shipped a new locations services in Play
Services called the Fused Location Provider.
Since these libraries
live in another application, you must actually have that application
installed. This means that only devices with the Play Store app
installed and up to date will be able to use your application.
So the conclusion is:
You need to test the app on your device as mentioned above.
Since you are using Fused Location Provider Api, that means the Api will automatically determine last location from one of the following sources:
GPS radio
Coarse points from cell towers
WiFi connections
So you could easily remove the GPS if condition from your code
Be a ware of that if you must use GPS signal, you need to be out side the building, lab, home or office.
If you want to dig more find more in the mentioned resources and there is a lot of online resources.
Resources: The first part of the answer, the source of it is from:
Android Programming: The Big Nerd Ranch Guide 2nd edition chapter 31 page 552 under Google Play Services

Mock coordinates Android Marshmallow

In my app I am using Android Location Manager API and I have a requirement of identifying whether the location coordinates are from normal Location Manager or if they are from Fake(Mock) Location provider. I used location.isFromMockProvider(). Once I turn on the fake location providing app, isFromMockProvider() method returns me true. And after that it does not matter if I turn, fake location providing app, on or off isFromMockProvider() method always returns true.
I found that once FakeGPS app, once triggered, overrides the location manager coordinates and once I stop the FakeGPS app, the Location Manager does not start collecting correct coordinates.
Is there something I am missing.

Disappointed with no response but I am glad that I got it working :)
Posting the resolution as it might help someone else.
Once the FakeGPS app starts mocking location, it stops my app's Location manager.
Now even if I stop the FakeGPS app mocking service, the location manager of my app won't trigger back.
I have to detect the event and restart the location manager of my app, after removing any test provider and clearing test locations.

just resetting and removing test location should help
String t = LocationManager.GPS_PROVIDER;
locationManager.clearTestProviderEnabled(t);
locationManager.clearTestProviderLocation(t);
locationManager.clearTestProviderStatus(t);
locationManager.removeTestProvider(t);

Android - New Location / Geofences APIs

I've tried to run Geofences sample and I've got little confunsed regarding to how it works.
Prior to go on, I've studied the new APIs and wached this video:
http://www.youtube.com/watch?v=Bte_GHuxUGc&list=WLRNCZT9Eq_HTG5jIEFxMpdqoXZBNalekx
So I jumped coding it. I thought that this API would manage the GPS position's captures automatically, in order to get my position.
So at this point raises my doubt. I've only got notified within a geofence, if I turnned my google map app on so my device starts capturing my location thru GPS.
So, what should I do to have "my app" forcing GPS use ?
I appreciate your help.
Best Regards,
Marlus

Check if Location is unavailable in Android Location Client

I would like to check if Location Client is able to provide any location. Is there any way to do so, apart from calling normal location system service?

The accepted answer was correct at the time. But in recent times things have changed with the availability of the SettingsApi It allows you to check if the location services are available on the device and there is a complete example provided by google on github that shows how to use this API. The sample code will prompt the user to enable location if it's switched off.

AFAIK, there is no method to check availability.
Possible Reason:
LocationClient uses fused API which gives location with appropriate combination of GPS,WiFi,Cell,Sensors (according to the Priority you have set for retrieving location).
Reference:
Fused API - Beyond the blue dot
Alternate Solution:
You already know it.you can check availability of provider by using location system service and LocationManager

How to turn on and turn off (enable and disable) Location Services programatically in ICS?

I'd like to know if it possible to enable and disable Location Services programatically in Android 4.0?
I've found several approaches how to do this for previous versions of Android (for instance, this is the most popular link). But these approach does not work for Android ICS.
Also, I understand that an application should not do this but, for instance, default widget does this.
Can anybody clarify if it is possible and how to achieve this?

In a tiny app I have developed, I turn off the gps by just disabling the location on the MyLocationOverlay. Of course, this will work only if you are using maps from Google as that class belongs to the Google API's.
myLocationOverlay.disableMyLocation();
I place the line on the onStop() method and only if it is currently enabled. And every time my app goes to the background, the GPS turns automatically off.
Hope it helps.

You can enable and disable gps device but users must confirm in setting widget.
The solution in this topic.

LocationManager L = (LocationManager) getSystemService(LOCATION_SERVICE);
if (!L.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
Intent I = new Intent(
android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(I);
}