I looked at this Q&A here: GoogleApiClient is throwing "GoogleApiClient is not connected yet" AFTER onConnected function getting called
As it seemed to
Your class must implement GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener and override all the methods.
GoogleApiClient will communicate with the LocationServices and give you the users latitude and longitude.
In your OnCreate() method build a GoogleApiClient that uses the desired api.
In your onStart() method start connecting the GoogleApiClient.
On the Sucessfull connection OnConnected() method is called where we will be making our LocationRequest.
Watch here for tutorial Android Location API Using Google Play Services