@Override
  protected void onPostCreate(Bundle savedInstanceState) {
    super.onPostCreate(savedInstanceState);
    getActivityHelper().setupSubActivity();

    ViewGroup detailContainer = (ViewGroup) findViewById(R.id.fragment_container_module_detail);
    if (detailContainer != null && detailContainer.getChildCount() > 0) {
      findViewById(R.id.fragment_container_module_detail).setBackgroundColor(0xffffffff);
    }
  }
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.modules);

    ModuleDetailFragment moduleDetailFragment =
        (ModuleDetailFragment) getSupportFragmentManager().findFragmentByTag("module_detail");
    if (moduleDetailFragment == null) {
      moduleDetailFragment = new ModuleDetailFragment();
      moduleDetailFragment.setArguments(intentToFragmentArguments(getIntent()));

      getSupportFragmentManager()
          .beginTransaction()
          .add(R.id.fragment_container_module_detail, moduleDetailFragment, "module_detail")
          .commit();
    }
  }