(please give me an answer, if this is not what you intend the editor to do)
Not exactly, but the screenshot was probably a bit misleading...
So, when I open a source file in Xcode, it shows in the top bar the files place in the file hierarchy (eg. Lite Foundation -> Sources -> LFString.c) plus the function where the cursor is currently in (or pragma or define).
This looks like this:

When I now click on the function in this top bar, it shows me a drop down list with all functions/pragmas/defines in the file which is really handy to get a overview of a new file or to jump to other functions especially in large files.
I don't want the whole bar but this one feature to jump to different locations in the file.
(I hope it was a bit clearer now)