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How to enforce my geo location is real GPS, not just my network endpoint's passive location?

We have in-house tablets, that we control, and we have the requirement that their recorded location be as accurate as possible. I do everything I should to turn on real GNSS GPS, but getLastKnownLocation("gps") always returns null.
We use a Samsung Galaxy Tab A7, SM-T500, whose specifications swear it has a real GPS GNSS radio receiver. Google Maps identifies my secret lair correctly.
Our AndroidManifest.xml requests GPS permissions:
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<activity
android:name=".MainActivity"
android:foregroundServiceType="location"
...
>
In the tablet's Settings, our app has Location permission "Only while app is in use," which is fine because our app dominates our tablet and is interactive. Our tablet is not used in a vehicle, so the location only needs to be accurate within the last 10 minutes or so.
locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER) returns true, as does that call with PASSIVE_PROVIDER and NETWORK_PROVIDER. The "fused" provider is not available.
Then we call this, to pull every kind of location and return the most accurate one:
private static Location getLastKnownLocation(#NonNull LocationManager locationManager) {
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())
bestLocation = l; // Found best last known location: %s", l);
}
return bestLocation;
}
All we get is "passive." Do GPS locations specifically require a round-trip thru locationManager.requestLocationUpdates(), or is getLastKnownLocation() good enough?

Similar answers are elsewhere but this thread deserves closure. It seems getLastKnownLocation() does not work with GPS and GNSS satellites, so as Phantom Lord prompted the correct fix is to enable my main activity for GPS:
public class MainActivity extends AppCompatActivity implements LocationListener {
Then in onCreate() turn on a listener:
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
if (locationManager != null) {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return; // TODO spank user
}
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 3000, 10, this);
}
Then catch the updates:
private Location gpsLocation = null;
#Override
public void onLocationChanged(Location location) {
gpsLocation = location;
}
Now a new question: Why is the passive location accuracy ~5 meters while the GPS location accuracy is ~14 meters? This is a naive tablet, so it certainly doesn't know my home address and such. According to my internet spam, my IP address is in a nearby city...

finding current location in android through GPS

Is there possible to get accurate latitude and longitude of a user through "GPS" after changing its location of very shorter distance like 3-4 feet.
Actually I have made an application in android which gives me latitude and longitude of a user but, it changes its value on a same point or location of a user.
Kindly help me out of this problem.
thanks in advance.

My Experience says It depends on Phone/Device you are using, if your device support AGPS then getting GPS coordinates will be easier and fast (No related to your coding skill as you will be using android SDK). Normal GPS also return accurate data, try downloading Savaari application from google play, It works like charm, your 2nd Question Yes it is possible to get coordinates after a specific time or distance interval, when ever you are registering your listner you have to provide time and distance (in Meters) after which you want to receive GPS Value.
Check out this snippet : -
public void startReadingGPS(int readAfterMinimumTime, int readAfterMinimumDistance ){
locationManager = (LocationManager)mContext.getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, readAfterMinimumTime, readAfterMinimumDistance, this);
}
public void requestLocationUpdates (String provider, long minTime, float minDistance, LocationListener listener)
Added in API level 1
Register for location updates using the named provider, and a pending intent.
See requestLocationUpdates(long, float, Criteria, PendingIntent) for more detail on how to use this method.
Parameters
provider the name of the provider with which to register
minTime minimum time interval between location updates, in milliseconds
minDistance minimum distance between location updates, in meters
listener a LocationListener whose onLocationChanged(Location) method will be called for each location update

you should implement locationlistener in your activity
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // 10 meters
// The minimum time between updates in milliseconds
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1; // 1 minute
boolean isGPSEnabled = false;
LocationManager locationManager = (LocationManager) yourapplicationcontext
.getSystemService(LOCATION_SERVICE);
// getting GPS status
isGPSEnabled = locationManager
.isProviderEnabled(LocationManager.GPS_PROVIDER);
if (isGPSEnabled) {
if (location == null) {
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("GPS Enabled", "GPS Enabled");
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
}
//Add this permission
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />

Why does the LocationManager does not have a lastKnown location?

I want the location of user and that too just once after that user navigates on his own
locationManager = (LocationManager)this.getSystemService(LOCATION_SERVICE);
location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
System.out.println(location.toString());
lat=location.getLatitude();
lng=location.getLongitude();
}
p = new GeoPoint((int) (lat * 1E6), (int) (lng * 1E6));
However i am not able to get the location of the user is it because of slow internet connection from the mobile ??

The getLastKnownLocation method will only return a location if the gps LocationProvider has stored a location somewhere. If the user has not yet used the gps on his device long enough to obtain a valid GPS fix the method will return null.
Even if you retrieve a location check the time of the location, there is no guarantee that the location isn't very very old.

It's not enough to just get a locationManager and call getLastKnownLocation()
because until there is an update there will be no "last known location"
You are missing that request provided by the LocationManager class:
public void requestLocationUpdates(java.lang.String provider,
long minTime,
float minDistance,
android.location.LocationListener listener)
If your activity implements LocationListener as mine did, you can pass in "this" as the LocationListener for a call originating in a method of that class. Otherwise, there are several other overloads taking Activity or Looper classes instead.
locationManager.requestLocationUpdates(provider, minTime, minDistance, this);
In order to make sure the device is getting a location, request updates - but you also may
want to put guards for failure to find providers or getLastKnownLocation returning null.
locationManager.requestLocationUpdates(provider, 1, 0, this);
mostRecentLocation = locationManager.getLastKnownLocation(provider);
if(mostRecentLocation == null)
// lower your expectations, or send user message with Toast or something similar
Tell the user to turn on their location sharing or other provider services.

disable GPS signal during location update

I am making location tracker application in android so I call a function
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,
30000,
0,
listener);
So in this example i set 5minute interval.
Now my question is why GPS signal is constantly activate, though my interval time is 5minute..
Can't is deactivate till 5 minute and after 5 minute can't it automatically activate??
I thing device require more battery power though it constant active...
What I have to do to deactivate GPS for particular interval defined in function.

No you can't but you can always run a service that asks for a single shot fix every five minutes.
For e/g use requestSingleUpdate (String provider, PendingIntent intent)
To broadcast an intent when a single shot fix is obtained.

I had exactly the same problem with my app. I used a timer initialized on startup:
serviceHandler = new Handler();
serviceHandler.postDelayed( new RunTask(),1000L );
This runs locupdate and adds one to counter every second.
class RunTask implements Runnable {
public void run() {
++counter;
locupdate(0,0);
serviceHandler.postDelayed( this, 1000L );
}
}
this is the locupdate function used above. Note, mlocManager is defined globaly as a LocationManager.
public void locupdate(int minTime, float minDistance) {
mlocManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
mlocListener = new MyLocationListener();
if (mlocListener != null && mlocManager != null) {
mlocManager.removeUpdates(mlocListener);
}
mlocManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,
minTime, minDistance, mlocListener);
}
One last thing. At the end of the onLocationChanged method in LocationListener I remove updates after 5 locations fixes:
mlocManager.removeUpdates(mlocListener);
This is similar to requestSingleUpdate() but i find it more flexible. Hope this helps!

Basically this function takes time interval as follows,
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 30000, 0, listener);
the meaning over here is that give me GPS update if you found within the given time with no
other priority tasks.
so this is you method
public void requestLocationUpdates (long minTime, float minDistance, Criteria criteria, PendingIntent intent)
& these are the parameters, please read it carefully you can understand it
Parameters
minTime = the minimum time interval for notifications, in milliseconds. This field is only used as a hint to conserve power, and actual time between location updates may be greater or lesser than this value.
minDistance = the minimum distance interval for notifications, in meters criteria contains parameters for the location manager to choose the appropriate provider and parameters to compute the location
intent = a {#link PendingIntent} to be sent for each location update
That is all about
Best Regards,
~Anup

Android: How to keep GPS active until more accurate location is provided?

I am using the location manager's requestLocationUpdates() method to receive an intent to my broadcast receiver periodically. The system is correctly firing the intent to my receiver, and I have been able to use it correctly. The only problem is that the GPS location provider only stays active for a few seconds after the initial location acquisition, and I need it to stay on a little longer so that the location estimates are more accurate.
My question is how to make the GPS location provider stay active for each periodic request that comes from the LocationManager requestLocationUpdates. Does anyone know how to do this?

Try something like this. I think it is the right approach
private void createGpsListner()
{
gpsListener = new LocationListener(){
public void onLocationChanged(Location location)
{
curLocation = location;
// check if locations has accuracy data
if(curLocation.hasAccuracy())
{
// Accuracy is in rage of 20 meters, stop listening we have a fix
if(curLocation.getAccuracy() < 20)
{
stopGpsListner();
}
}
}
public void onProviderDisabled(String provider){}
public void onProviderEnabled(String provider){}
public void onStatusChanged(String provider, int status, Bundle extras){}
};
}
private void startGpsListener()
{
if(myLocationManager != null)
// hit location update in intervals of 5sec and after 10meters offset
myLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 5000, 10, gpsListener);
}
private void stopGpsListner()
{
if(myLocationManager != null)
myLocationManager.removeUpdates(gpsListener);
}

if you keep your LocationListener active, it should continue to receive updates to onLocationChanged() if the fix accuracy narrows. and indeed location.getAccuracy() will tell you the current accuracy
maybe set minTime and minDistance both to 0 to receive updates with greater frequency? will use more battery, but is more preise.

There is a example about get GPS location with timeout.
http://sikazi.blogspot.com/2010/09/android-gps-timeout.html#more

To get GPS location periodically, get the location from onLocationChanged method of locationListener and in onResume method specify the timing in milliseconds for getting periodic updates
onResume
location_manager.requestLocationUpdates(provider, 1000, 1, MainActivity.this);