GLKViewController not in the "subclass of" list

Maybe it is a problem only happens on my machines, lion  with xcode 4.3.3 from app store.

I create an empty project and try to add a file to be the subclass of GLKViewController. But I can not find it in the drop list. I can paste it into the blank anyway. Then the new files are nearly blank, instead of being with some initial codes.

Here is my solution. #import <GLKit/GLKit.h> some where. Reload the the project to make it re-index. Then I will find GLKViewController in the list.