making a gui editor
c, c++, linux, xml
Solution
I would recommend that you not try to build your own GUI builder. It is a daunting task that you will not be able to accomplish as a school project. C++ is fully-compiled, which means that it lacks almost every feature that enables people to build meta-tools (like GUI editors) for it. This mainly has to do with the fact that C++ does not have runtime reflection (natively, anyway). Beyond that, there is no "one GUI toolkit and/or paradigm to rule them all." This makes your problem incredibly difficult to deal with.
So: I would recommend Qt, because it works on a ton of platforms, is easy to use and is just plain awesome. You could also look at the billions of other GUI toolkits like Gtk+, Tk, FLTK, YAAF, GLUI, dlib, CLX...
I'm aware that this does not actually answer the question. However, I do not think that the author is aware of how incredibly difficult the task he has set in front of himself is.
Problem
For my school project, I would like to build a gui that someone else can use to create a gui. Upon some research I saw lot of gui builders but didn't see anything along the lines of what I am looking for. But then I did find a tutorial using C# on here I rather create this gui editor for linux environment. Any suggestions to where I should start? what tools I can use? Any links to any tutorials? Any help/direction would be greatly appreciated. P.S. I would like to add that it only needs to be very simple. like few text input fields and some button type fields that user can arrange in the order desired.