Basically i would like to see hod the classes are organized and how GUI functions with code behind.

I need good, tutorial, document or book where i can read/learn more about code design patterns for desktop applications in C++.

Also if there is good open source project to learn more about that it would be very very helpful.

Preferable type of application is app that works with database, enter some data to database and give some output.

I prefered Qt but also wxwidgets would be great.

Platform preferable for Linux.

Thank you very much.