FragmentManagerActivity.java

   public void showFragment(ParentFragment fragment, int transition, int containerViewId) {
        FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
        if (containerViewId == NO_CONTAINER) {
            containerViewId = R.id.activity_root;
        }
        if (currentFragment == null) {
            fragmentTransaction.add(containerViewId, fragment);
        } else {
            fragmentTransaction.replace(containerViewId, fragment);
        }
        fragmentTransaction.setTransition(transition);
        addToBackStack(fragment.getClass().getName(), fragmentTransaction);
        fragmentTransaction.commit();
        currentFragment = fragment;
    }