GetLastLocation() Always Null In GoogleApiClient
Solution 1:
You need to call requestLocationUpdates()
in order to register the listener and have onLocationChanged()
invoked.
Be sure to un-register the listener as soon as possible to avoid excessive battery drain.
Also note that the getLastLocation() method can and will return null. The main problem is that it doesn't prompt a request to the OS for a new location lock, instead it just checks if there was a last known location from some other app's location request. If no other app had recently made a location request, then you get a null location returned to you.
The only way to guarantee that you actually get a location is to request one, and this is done with a call to requestLocationUpdates().
Here is a working example for reference:
public class MainActivity extends FragmentActivity
implements OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener,
LocationListener {
private GoogleMap map;
private LocationRequest mLocationRequest;
private GoogleApiClient mGoogleApiClient;
private Location mLastLocation;
private Marker marker;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@Override
protected void onResume() {
super.onResume();
buildGoogleApiClient();
mGoogleApiClient.connect();
if (map == null) {
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
}
}
@Override
public void onMapReady(GoogleMap retMap) {
map = retMap;
setUpMap();
}
public void setUpMap(){
map.setMapType(GoogleMap.MAP_TYPE_HYBRID);
map.setMyLocationEnabled(true);
}
@Override
protected void onPause(){
super.onPause();
if (mGoogleApiClient != null) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
}
}
protected synchronized void buildGoogleApiClient() {
Toast.makeText(this, "buildGoogleApiClient", Toast.LENGTH_SHORT).show();
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
}
@Override
public void onConnected(Bundle bundle) {
Toast.makeText(this,"onConnected",Toast.LENGTH_SHORT).show();
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(1000);
mLocationRequest.setFastestInterval(1000);
mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
//mLocationRequest.setSmallestDisplacement(0.1F);
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
@Override
public void onConnectionSuspended(int i) {
Toast.makeText(this,"onConnectionSuspended",Toast.LENGTH_SHORT).show();
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
Toast.makeText(this,"onConnectionFailed",Toast.LENGTH_SHORT).show();
}
@Override
public void onLocationChanged(Location location) {
mLastLocation = location;
//remove previous current location Marker
if (marker != null){
marker.remove();
}
double dLatitude = mLastLocation.getLatitude();
double dLongitude = mLastLocation.getLongitude();
marker = map.addMarker(new MarkerOptions().position(new LatLng(dLatitude, dLongitude))
.title("My Location").icon(BitmapDescriptorFactory
.defaultMarker(BitmapDescriptorFactory.HUE_RED)));
map.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(dLatitude, dLongitude), 8));
}
}
One more thing, if your map is in a Fragment, there is no need to have a nested SupportMapFragment. You can just have your Fragment extend SupportMapFragment. This removes the need of having a nested Fragment, and you don't even need to inflate any layout xml, here is a simple example:
public class MapTabFragment extends SupportMapFragment
implements OnMapReadyCallback {
private GoogleMap mMap;
private Marker marker;
public MapTabFragment() {
}
@Override
public void onResume() {
super.onResume();
setUpMapIfNeeded();
}
private void setUpMapIfNeeded() {
if (mMap == null) {
getMapAsync(this);
}
}
@Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
setUpMap();
}
private void setUpMap() {
mMap.setMyLocationEnabled(true);
mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
mMap.getUiSettings().setMapToolbarEnabled(false);
mMap.setOnMapClickListener(new GoogleMap.OnMapClickListener() {
@Override
public void onMapClick(LatLng point) {
//remove previously placed Marker
if (marker != null) {
marker.remove();
}
//place marker where user just clicked
marker = mMap.addMarker(new MarkerOptions().position(point).title("Marker")
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA)));
}
});
}
}
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