When I close the dialog, I call a method that invoke from the DialogFragment:
invalidateOptionsMenu();
then, it enters in the onPrepare Method :
@Override
public boolean onPrepareOptionsMenu(Menu menu) {
MenuItem menuSync= menu.findItem(R.id.menu_sync);
int sincronizado = prefs.getInt("sincronizado", 0);
if (sincronizado == 1)
menuSync.setIcon(R.drawable.ic_action_update_red);
return super.onPrepareOptionsMenu(menu);
}