LocationActivity.java

public class LocationActivity extends AppCompatActivity implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener {

    private GoogleApiClient googleApiClient;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        googleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this) //Be aware of state of the connection 
                .addOnConnectionFailedListener(this) //Be aware of failures
                .build();

        //Trying to connect with Google API. If it works onConnected() will be called, else onConnectionFailed() will be called.
        googleApiClient.connect();

    }

    @Override
    protected void onStop() {
        super.onStop();
        stopGoogleApiConnection();
    }

    public void stopGoogleApiConnection() {
        //Stopping the Connection
        if (googleApiClient.isConnected()) {
            googleApiClient.disconnect(); //Closing connection with Google APIs
        }
    }

    /**
     * After calling connect(), this method will be invoked asynchronously when the connect request has successfully completed.
     * After this callback, the application can make requests on other methods provided by the client and expect that no user intervention
     * is required to call methods that use account and scopes provided to the client constructor.
     *
     * @param bundle
     */
    @Override
    public void onConnected(Bundle bundle) {
        //Google API connection has been done successfully
    }

    /**
     * Called when the client is temporarily in a disconnected state.
     * This can happen if there is a problem with the remote service (e.g. a crash or resource problem causes it to be killed by the system).
     * When called, all requests have been canceled and no outstanding listeners will be executed.
     * GoogleApiClient will automatically attempt to restore the connection.
     * Applications should disable UI components that require the service, and wait for a call to onConnected(Bundle) to re-enable them.
     */
    @Override
    public void onConnectionSuspended(int i) {
        //Wait for the GoogleApiClient restores the connection.
    }

    /**
     * Called when there was an error connecting the client to the service.
     *
     * @param connectionResult
     */
    @Override
    public void onConnectionFailed(ConnectionResult connectionResult) {
        //Google API connection has been failed! Stop it and warn!
        stopGoogleApiConnection();
    }
}