Get location updates using location client and location request with GPS only - android

In my app i get location updates using location client and location request. And i implement GooglePlayServicesClient.ConnectionCallbacks,
GooglePlayServicesClient.OnConnectionFailedListener,
com.google.android.gms.location.LocationListener. And my app work like a champ.
My question is: When GPS fix a location The onLocationChanged(Location location) called. What's happen when GPS lost signal?. How i can handle this case with Location client??

The new Location Api gets the best location using the sensors(gps, wifi, etc) on your phone and you do not need to worry from which provider it is getting the location. So, you do not need to handle that. On the callback or in the pending intent, it will return the best location when you'll need according to the setInterval() & setFastestInterval() that you have specified.
This video link might help in the clear understanding of how simple the api is.
https://www.youtube.com/watch?v=Bte_GHuxUGc&spfreload=10%20Message%3A%20Unexpected%20end%20of%20input%20(url%3A%20http%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DBte_GHuxUGc)

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is FusedLocationProviderApi.getLastLocation is HIGH_ACCURACY?

I want to ask if getLastLocation() from FusedLocationProviderApi get Location with HIGH_ACCURACCY or not?
when I read the documentation, it says:
public abstract Location getLastLocation (GoogleApiClient client)
Returns the best most recent location currently available.
If a location is not available, which should happen very rarely, null will be returned. The best accuracy available while respecting the location permissions will be returned.
This method provides a simplified way to get location. It is particularly well suited for applications that do not require an accurate location and that do not want to maintain extra logic for location updates.
does the best means get the most accurate location? or like automatically request last location using LocationRequest.PRIORITY_HIGH_ACCURACY?
getLastLocation will not create a new request to get the current location. It gives already available/saved location based on previous location request.
This already available/saved location details is based on the last location data requested by any client/app on the user's device.
Eg: If user has Google Maps installed and running , it gives you the accurate location of the device. In this case once you start your app and check for last location it will give you location with high accuracy.
In case your device doesn't have Google Maps but another app which requested location updates with low accuracy , your getLastLocation will return that low accuracy location .

Android fused location api not providing consistent updates with screen off

I have some code that runs multiple times per second in my app. I'm trying to get my location in every cycle. I am using the following:
Location myLastPos = LocationServices.FusedLocationApi.getLastLocation(googleApiClient)
My app also runs in the background using a PARTIAL_WAKE_LOCK. With the screen on everything seems OK. When I turn the screen off my app still runs normally but I no longer get location updates consistently.
It appears that I get updates much less frequently (often minutes in between updates). I'm checking the timestamp of the location using:
myLastPos.getElapsedRealtimeNanos()
I also found that even when the screen is on I get some strange results. Sometimes I get a few milliseconds between updates, other times I get a few seconds. This is all very concerning. Can someone either help me use FusedLocationApi properly or suggest an alternative. All I really want is to poll the gps directly for lat/long a few times a second without google libraries getting in the way.
The getLastLocation() method just gets the last known location that the device happens to know. The "last known location" here means exactly that: It may not be up-to-date. Locations do come with a time stamp which could be used to asses if the location might still be relevant.
The device doesn't determine its location on its own, but only when some application request the location. So your app is now dependent on other applications requesting location updates.
If you need updates every few seconds, then request regular location updates yourself.
Android documentation recommends the FusedLocationProvider, but the LocationManager is also a perfectly valid option, if there's any reason to avoid the Google Play services.
The basic idea is to first request location updates:
// Using LocationManager as an example.
mLocationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
// Using GPS, requesting location updates as soon as available and even for
// the smallest changes. Here 'this' refers to our LocationListener
// implementation.
mLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this);
The updates are then received by a listener:
#Override
public void onLocationChanged(Location location) {
// We received a location update.
// Copy the value from the method parameter to our
// class member variable.
mLocation = location;
}
And when you no longer need the updates you should cancel the request:
mLocationManager.removeUpdates(this);
The approach is very similar for the FusedLocationProvider.

what if LocationListener.onLocationChanged is not called?

In my android app, I am making use of google play's location services for determining device location.So I am implementing com.google.android.gms.location.LocationListener's onLocationChanged method. But based on device's location settings, it is very much possible that this method is not even called.For eg, if user has set 'Device Only' option then only GPS based location access is available,and if user is indoor GPS wont work and onLocationChanged() is not called.
I want to know how to come to know of this at run time so that alternate action can be suggested to user?
From the document itself, LocationListener is used for receiving notifications from the LocationManager when the location has changed. These methods are called if the LocationListener has been registered with the location manager service using the requestLocationUpdates(String, long, float, LocationListener) method.
Also check this blog to understand more about LocationListener in Android. It also explains here the status and behavior of a GPS and some sample code that serve as a guide for you. I hope it helps you to know more about LocationListener

Create an android app that obtains & sends GPS location of user in background

Sir,
I want to create such an android app that:
First,When we open that app,Then it Starts a background service and,
Then gets GPS location of user.
After that, It POSTS (POST Method of HTTP) the returned LATTITUDE and LONGITUDE to PHP Page.
If someone genius can provide me link to do all these,
I will highly greatful to his/her......
This is not a platform to ask such broad questions. But as I have just finished an exact implementation, I can give you hints and links to complete your task.
Servies: As you are probably already aware, you will need to have a service to send GPS data in background.
Location Listener: Location listener helps you listen the location of a user. It provides a method onLocationChanged(Location location) which will be fired anytime the location of user is changed on given conditions.
For your third task, use your API and send latitude and longitude from the location object provided by onLocationChanged(Location location) with the help of location.getLatitude() and location.getLongitude().

getLastKnownLocation is not the actual location

In my app I have an AlarmManager set to run an IntentService every so often to make a WebService Call to my server sending your current location
When the alarm is started I also start a Service that has a LocationManager to keep track of the location locally.
When I make the web service call to my server I use
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
String provider = locationManager.getBestProvider(criteria, true);
Location lastKnownLocation = locationManager.getLastKnownLocation(provider);
since I only need the location at this point in time and the next time the web service is called again I just get it again. But it appears even though I have a service running in my background that uses the GPS and gets the right location, calling
locationManager.getLastKnownLocation(provider);
when I make the web service to get the location it gives me a stale location and not the current one. Now I would think that since I already have a locationmanager running in another service that the getLastKnownLocation would get updated to the correct location everytime the onLocationChanged gets called but that is obviously not the case which makes no sense to me.
So my question now is how can I get my correct location in my IntentService since I cannot rely on getLastKnownLocation
I do no need to know the location everytime it changes I just need to know what it is at the time I make the web service call so starting another location manager does not seem like a good idea. The only thing I can think of to solve this is to store the location from my other service in SharedPreferences and just grab whatever is in there but that seems a little hacky and i dont like hacky.
any ideas?
The last known location for android gets updated only when any app requests for a location (app can be yours or any other on the device). You have to implement the location listener and then use locationManger.requestLocationUpdates(provider, minTime, minDistance, locationListener) to ask for the location update. The android system will get the location update on your request and set the lastKnownLocation for all apps to use.
The only reason I can think of the lastKnownLocation not being set is that the android system couldn't get the location. Check that the provider requested for the location update is enabled. Also you can use Passive Provider for piggybacking on the location requests of other apps and actively look for location only if there is no update for certain time out period (This approach should be better that constantly trying to get location updates which are costly).

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