MainActivity.java

package co.ortizol;

import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;

import com.google.android.gms.auth.api.Auth;
import com.google.android.gms.auth.api.signin.GoogleSignInResult;

import co.ortizol.fragments.InicioSesionFragment;

/**
 * Representa la actividad principal y host de fragmentos de la aplicación.
 */
public class MainActivity extends AppCompatActivity {

    private static final String TAG = MainActivity.class.getSimpleName();
    private Toolbar toolbar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        toolbar.setSubtitle(getString(R.string.inicio_sesion));
        getSupportFragmentManager().beginTransaction()
                .replace(R.id.layContenedor, new InicioSesionFragment(), "INICIO_SESION_FRAGMENT")
                .commit();
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        Fragment frg = getSupportFragmentManager().findFragmentByTag("INICIO_SESION_FRAGMENT");

        Log.i(TAG, "MainActivity:OnActivityResult; requestCode: " + requestCode);

        if (frg instanceof InicioSesionFragment) {
            if (requestCode == InicioSesionFragment.SIGN_IN_GOOGLE_REQUEST_CODE) {
                Log.i(TAG, "MainActivity:OnActivityResult:SIGN_IN_GOOGLE_REQUEST_CODE");
                GoogleSignInResult result = Auth.GoogleSignInApi.getSignInResultFromIntent(data);
                ((InicioSesionFragment) frg).handleSignInResult(result);
            } else {
                Log.i(TAG, "MainActivity:OnActivityResult:FACEBOOK");
                frg.onActivityResult(requestCode, resultCode, data);
            }
        }
    }
}