With the Qt environment there is a build setup with it’s own tool-chain (located in your “C:\Qt\4.8.4\bin” folder).
I’ll briefly cover the key components here:
The most basic C++ object most everything is derived from is the “QObject” class, then from there the QWidget class is the base class of all user interface objects that you’ll see a lot of it. Another key one is QApplication but since we’re making plug-ins we’ll only need to occasionally reference IDA’s own instance of this class.
When you work with UIs with Qt you’ll want to use the Qt designer. It’s a UI design tool similar to what’s in VS (Visual Studio) with it’s dialog and forums editors.