The function of the .xml file is to define the structure to be created, panel, buttons, etc., set the event trigger, and establish a reference to the .lua file. The .lua file contains a variety of functions that trigger different events. 1. The message processing function is virtual function in the CWND class?
2.cview :: Ondraw () can print something in the printer, how is the CDC base class pointer to Derived Clase? Ondraw is on OnPaint call, in OnPaint, CClientDC DC (this); The Clientdc is created for the cView, Always
