QT or others for the beginning linux programmer

I'm an experienced Win32 guy and I know a tad bit about other windows interfaces such as MFC. I want to learn linux programming. On opening KDevelop in KDE I created and compiled the wizard generated MDI application. It looks great to me although I had to modify the code slightly to get it to run. It seems that the friend classes it declared left out the keyword "class". Strange but I'm not really concerned about the wizard right now. What is of interest is the library it used. QT. Obviously this is a C++ specific thing and is probably not the lowest level API. So, here's my questions:

1. Is QT like MFC in that it wraps the API?
2. What are the API's for linux/KDE/Gnome/X etc..?
3. I'm used to VC++ commands such as "Go to definition" and "Go to reference", does something similar exist in KDevelop? I figured out global searches already, but that's not good enough really. I wanted to see the QT classes but couldn't figure out how to get to them.

Thanks guys.

1. Yes, QT/GTK/Athena/Motif use Xlib to draw their widgets for you.

2. Linux is an OS, it does not havea GUI API, KDE uses QT + it's own libs, Gnome uses GTK/gtkmm. X is a loaded letter. Xlib is the lowest API you can use.

3. Never used kdevelop. However cscope can be used to find definitions/declarations.

XLib then? I think I'd rather work at that level. I'm accustomed to working with Win32 API and I make my own wrappers. I am looking to write portable code through my wrapper classes and implement my existing wrappers for XLib. Can I work strictly in XLib and standard C++ to pretty much accomplish anything on there?

As far as Linux being an OS, I suppose the OS line has been obscured by microsoft. I'm used to referring to the various DLLs as part of the windows OS. Perhaps that's not technically correct but it is what I meant..

What about this "Anjuta" or whatever it is? Is that a better IDE?

www.anjuta.org
it's actually mainly designed for use with GNOME rather than KDE, but is fairly similar to KDevelop - i'd suggest trying it and seeing for yourself if you like it any better/worse :)