In my app I am using location services to obtain the user location coordinates to compare the distance to the objects which are obtained from my server.
So the user must have internet connection ON due to data obtained from server.
So in that case, I decided not to use GPS_PROVIDER, but only NETWORK_PROVIDER for user location, as the user needs to have internet connection, and this is quicker as GPS.
isNetwork = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
Till now I checked if isNetwork exists then do the stuff for NETWORK_PROVIDER, else try GPS_PROVIDER.
Now the question is, if the internet connection is always on, do I still need also GPS_PROVIDER?
I just want to get rid of the part of code for GPS, so I want to be sure, if the user has internet connection ON, the NETWORK_PROVIDER will always work.
To shorten the question: does NETWORK_PROVIDER depend from active internet connection? Does the user need to enable the device location in Settings for using just NETWORK_PROVIDER and not GPS?
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I need accurate location updates. When using FusedLocationServices from GooglePlayServices, even if I set HighAccuracy, it will get locations from Wi-Fi and cellular when GPS is not available. How do I request locations ONLY from GPS, and with no updates coming in when GPS is not available?
Use LocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, ...)
this removed the need for GooglePlayServices.Location completely.
Some resources say getLastKnownLocation() merely gives a location of some previous app's Location Change Listener.
But one thing I feel is missing from the conversation -- if the phone has GPS enabled, isn't this GPS tracking/updating as the phone moves? So if I call getLastKnownLocation(), isn't it getting the current GPS from the phone's constantly-updated GPS?
If so, then why do people warn against using it / accuse it of potentially getting a "stale" location? If the GPS is being tracked / updated, and getLastKnownLocation() makes a one-time grab of it's current position, what makes getLastKnownLocation() bad?
What am I mistaken about the Locations service or GPS?
The documentation says: Returns a Location indicating the data from the last known location fix obtained from the given provider.
Also, about the "out of date location": This can be done without starting the provider. Note that this location could be out-of-date, for example if the device was turned off and moved to another location. ("This" refers to getting the last known location).
Also, taken from LocationProvider docs:
Each provider has a set of criteria under which it may be used; for example, some providers require GPS hardware and visibility to a number of satellites; others require the use of the cellular radio, or access to a specific carrier's network, or to the internet. They may also have different battery consumption characteristics or monetary costs to the user.
if the phone has GPS enabled, isn't this GPS tracking/updating as the phone moves?
Well, it is, but not constantly. This has to do with battery consumption, if the phone was constantly updating the GPS location, the battery life would suffer a lot. The GPS location is usually updated when some app requests it. But even that request is not guaranteed to succeed. For example, suppose your going into a tunnel. Some application requests to update the GPS coordinates right before entering the tunnel and it succeeds. Now, you've entered the tunnel, which is 5km long. Most probably your device won't be able to get a GPS fix from the tunnel, so for the next 5km (at least) getLastKnownLocation() will return an outdated value, since the devices last known location was at the entrance of the tunnel.
What you could do is explicitly request to update the GPS location, that however might take some time and there are no guarantees that it will succeed.
You have the assumption "if the phone has GPS enabled, isn't this GPS tracking/updating as the phone moves". This assumption is incorrect. The GPS functionality takes up a lot of battery life so it should be used sparingly and almost certainly not all the time.
I've developed an app that receives the location from both GPS_PROVIDER and NETWORK_PROVIDER, however the NETWORK_PROVIDER returns the best values retrieved from WIFI and GPRS, without having any control over it. I need to get the value returned by the GPRS location listener even when you have WIFI active, so I can use it to dismiss the fake locations from other apps.
Is it possible to do this?
At the moment I'm testing this solution Disable / Check for Mock Location (prevent gps spoofing) , I'll let you know if it solves my issue
Unfortunately it is not possible, no.
You can do something like this:
final LocationManager locationManager = getLocationManager();
final List<String> providers = locationManager.getProviders(true);
if (providers.size() > 1) {
providers.remove(LocationManager.NETWORK_PROVIDER);
}
But you don't have the option to distinguish between a cell or a wifi network-provider!
This provider determines location based on availability of cell tower
and WiFi access points. Results are retrieved by means of a network
lookup.
Constant Value: "network"
Source: http://developer.android.com/reference/android/location/LocationManager.html#NETWORK_PROVIDER
What you can try is to use this solution. However, since this doesn't seem to be documented I'd be careful relying on it because it might break in future OS versions or might not work on every device.
I am trying to get location based on GPS or network but the problem is that if I take based on GPS location it takes lot of time to fetch the location details. Hence I would like implement a method where if GPS signal is very low fetch location using network provider. How do I determine the GPS signal? if do there is problem with this? GPS signal is always low even in open sky and hence it would always get to network provider?
How do I fix this problem?
Are you polling the location with LocationManager.GetLastKnownLocation, or are you getting updates asynchronously via requestLocationUpdates?
For the first, query for the location with the GPS_PROVIDER. If it returns null, then query for NETWORK_PROVIDER
If you're getting notifications, request both. Then you can implement onStatusChanged to tell when the GPS is available or not, and ignore network updates if it is, or use them if not (the location object tells you what the provider was).
Adding lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, ll); it will start fetching the gps using networ. Using location.getProvider() you should be able to differentiate to know whether its gps or network.
I am using this code to get the location provider and location.
mLocationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
Criteria criteria = new Criteria();
mBestProvider = mLocationManager.getBestProvider(criteria, false);
mLocation = mLocationManager.getLastKnownLocation(mBestProvider);
If I turn off the GPS, the location is by network, but if I reboot the phone(so I loss the last position known) and with the 3G data connections off. So I am only using WIFI, I cant get any provider thus therefore any location. However google places app can locate me. I think it might be getting the lastknownlocation.But in that case my others applications should be able to get that location. Any idea whats happening?
The way you are calling this it will return all providers enabled or not because you are passing it false which is probably your intention but have you checked the return string?
mBestProvider = mLocationManager.getBestProvider(criteria, false);
You might be getting the gps provider, or you might be getting the network provider, I have learned not to trust the criteria mechanism because it seems to work differently per carrier and device (I have had some weird bugs reported because of this)
So I always ask specifically for gps and network providers and check last known for both, then use an algo to determine the best one to use.
The network provider can use cell or wifi hotspot/routers to determine location (google keeps a database of wifi information) so it's possible to get a fix with just wifi, not saying that is whats happening but it could be.
If that bears no fruit then it's possible that they are simply caching the last location update in preferences, some applications do that. To test the thesis, failing all of the above just leave the phone in that state and move to a very different location with the same properties if possible, should only take 2000 meters or so. If your app still reports null and places reports the old location you have your answer.
If places did report the newer location with wifi, and your app cannot (assuming you actually verify you are getting the network provider) then there is a chance they are using a private API via the Google Location Server (GLS) / MASF server via partial cell / wifi info but that's at the extreme end of the tin foil curve.