How to show my current location in Google Map Android using google API client

For targeting api-23 and higher:

See the answer here.

For targeting api-22 and lower:

Here is the full Activity code that does what you need, a modified version of my other answer here. It registers a location listener when the Activity loads, then when each location changed event occurs, it will add a Marker and also animate the map to center on the current location.

The key here is to wait until the onMapReady() callback has occurred before you request location updates.

Here is the full Activity code:

public class MainActivity extends AppCompatActivity implements
        OnMapReadyCallback, GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {

    LocationRequest mLocationRequest;
    GoogleApiClient mGoogleApiClient;

    LatLng latLng;
    GoogleMap mGoogleMap;
    SupportMapFragment mFragment;
    Marker currLocationMarker;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
        mFragment.getMapAsync(this);
    }

    @Override
    public void onMapReady(GoogleMap gMap) {
       mGoogleMap = gMap;
       mGoogleMap.setMyLocationEnabled(true);

       buildGoogleApiClient();

       mGoogleApiClient.connect();

    }

    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();
        Location mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
                mGoogleApiClient);
        if (mLastLocation != null) {
            //place marker at current position
            //mGoogleMap.clear();
            latLng = new LatLng(mLastLocation.getLatitude(), mLastLocation.getLongitude());
            MarkerOptions markerOptions = new MarkerOptions();
            markerOptions.position(latLng);
            markerOptions.title("Current Position");
            markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
            currLocationMarker = mGoogleMap.addMarker(markerOptions);
        }

        mLocationRequest = new LocationRequest();
        mLocationRequest.setInterval(5000); //5 seconds
        mLocationRequest.setFastestInterval(3000); //3 seconds
        mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
        //mLocationRequest.setSmallestDisplacement(0.1F); //1/10 meter

        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) {

        //place marker at current position
        //mGoogleMap.clear();
        if (currLocationMarker != null) {
            currLocationMarker.remove();
        }
        latLng = new LatLng(location.getLatitude(), location.getLongitude());
        MarkerOptions markerOptions = new MarkerOptions();
        markerOptions.position(latLng);
        markerOptions.title("Current Position");
        markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
        currLocationMarker = mGoogleMap.addMarker(markerOptions);

        Toast.makeText(this,"Location Changed",Toast.LENGTH_SHORT).show();

         //zoom to current position:
         mGoogleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng,11));

        //If you only need one location, unregister the listener
        //LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);

    }

}