Hi Raphael,
Thanks for your reply. I am sorry if you feel offended by "nerds", we use that a lot in my company.
I understand the way overrides works, thanks for your pointer. However, I still don't understand the following behavior:
Let's take Translate::getAdminTranslation() function as example.
It was called in AdminControllerCore::l() function, for translations of BO text fields. When I modify the return value in AdminControllerCore::l(), it shows in BO accordingly, everything makes sense. However, when I change the return value in TranslateCore::getAdminTranslation(), nothing happens. I even tried to delete the file /classes/Translate.php, everything still works properly.
It makes me feel I am not modifying the right file. But I can't find any other place which have getAdminTranslation() function defined.
Does what I described make any sense to you?
Thanks,
Henry