Rename a class in Xcode: Refactor… is grayed out (disabled). Why?

Question

Why is Refactor... grayed out (disabled) in Xcode?

I\'d like to rename a class.

Answer 1

I'm going to my project at finder, then change files name by get info.

After that, at xcode -> Project Navigator I delete the files.

At end, I click right on the class and Add files to ..., and add these files again.

It worked for me.