Recall variables from the onConnected method

I have a problem with some variables that I want to recover from an onConnected method, these variables contain the current latitude and longitude of my device and I want to recover them to store in a global variable and be able to use those global variables in the onMapReady method ( ).

This is my onConnected () method, the two variables I want to convert into global are txtLatitud and txtLength, here in this method they already have a value that is assigned by retrieving my current coordinates;

@Override
    public void onConnected(@Nullable Bundle bundle) {

        int leer = ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION);
        if (leer == PackageManager.PERMISSION_DENIED) {
            ActivityCompat.requestPermissions(this, PERMISOS, REQUEST_CODE);
        }

        ultimaPosicion = LocationServices.FusedLocationApi.getLastLocation(googleApiClient);

        if (ultimaPosicion != null){
            latitudActual = String.valueOf(ultimaPosicion.getLatitude());
            longitudActual = String.valueOf(ultimaPosicion.getLongitude());

            txtLatitud.setText(latitudActual);
            txtLongitud.setText(longitudActual);

        }

    }

And this is my onMapReady () method, the variables that I want to retrieve as global are to be used in that line of code:

  

final LatLng example = new LatLng (19.4188761, -99.1552811)

The problem is that I can not recover them as global, I tried to use this.test = txtLatidud , but the value that returns to me is null

 @Override
    public void onMapReady(GoogleMap googleMap) {

        final LatLng ejemplo = new LatLng(19.4188761, -99.1552811);




        Toast.makeText(this,"Latitud: " + prueba, Toast.LENGTH_LONG).show();

        googleMap.addMarker(new MarkerOptions()
                .position(ejemplo)
                .title("Prueba")
                .snippet("Población: 2,965 millones")
                .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN))
//                .alpha(.5f)
//                .flat(true)
                .draggable(true));

        googleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(ejemplo, 16));


    }

Complete code:

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

    private static final String[] PERMISOS = {
            Manifest.permission.ACCESS_FINE_LOCATION
    };

    private static int REQUEST_CODE = 1;
    private GoogleApiClient googleApiClient;
    private Location ultimaUbicacion;
    Double latitudObtenida;
    Double longitudObtenida;
    private TextView txtLat;
    private TextView txtLon;

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

         txtLat = (TextView)findViewById(R.id.txtLat);
         txtLon = (TextView)findViewById(R.id.txtLon);


        if (googleApiClient == null){
            googleApiClient = new GoogleApiClient.Builder(this)
                    .addConnectionCallbacks(this)
                    .addOnConnectionFailedListener(this)
                    .addApi(LocationServices.API)
                    .build();
        }

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



    }

    @Override
    public void onMapReady(GoogleMap googleMap) {
        int leer = ActivityCompat.checkSelfPermission(this,Manifest.permission.ACCESS_FINE_LOCATION);
        if (leer == PackageManager.PERMISSION_DENIED) {
            ActivityCompat.requestPermissions(this, PERMISOS, REQUEST_CODE);
        }


        final LatLng BUENOS_AIRES = new LatLng(-34.637936, -58.406372);

        googleMap.addMarker(new MarkerOptions()
                .position(BUENOS_AIRES)
                .title("Prueba")
                .snippet("Población: 2,965 millones")
                .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN))
//                .alpha(.5f)
//                .flat(true)
                .draggable(true));

        googleMap.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(latitudObtenida, longitudObtenida), 2.0f));

    }

    @Override
    public void onConnected(@Nullable Bundle bundle) {

        int leer = ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION);
        if (leer == PackageManager.PERMISSION_DENIED) {
            ActivityCompat.requestPermissions(this, PERMISOS, REQUEST_CODE);
        }

        ultimaUbicacion = LocationServices.FusedLocationApi.getLastLocation(googleApiClient);

        if (ultimaUbicacion != null){
            latitudObtenida = ultimaUbicacion.getLatitude();
            longitudObtenida = ultimaUbicacion.getLongitude();
        }

    }

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

    @Override
    protected void onStart() {
        googleApiClient.connect();
        super.onStart();
    }

    @Override
    public void onConnectionSuspended(int i) {

    }

    @Override
    public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {

    }
}