🚀 go-pugleaf

In article <8304@ncratl.AtlantaGA.NCR.COM> kso@ncratl.AtlantaGA.NCR.COM (Khun So) writes:
>
>
>    I have a couple of questions on Windows developement using C/C++ 7.0.
>    Any insights on the subjects will be greatly appreciated.
>
>
>        1. How does one extend MFC to support custom controls
>           and other window classes?  Specifically I would like
>           to derive a class from CWnd for the custom controls
>           I had developed.  Many of my controls use extra bytes
>           per window instance (cbWndExtra!=0 in WNDCLASS data
>           structure).  The current AfxRegisterWndClass always
>           sets cbWndExtra=cbClsExtra=0.  Is there a simple way
>           to do this without modifying MFC source?
Let's say you have a Window class called "MYCLASS", then all you
need to do to have a C++ class is the following:

class CMyClass : public CWnd
{
public:
	BOOL Create(LPCSTR lpszWindowName, DWORD dwExtraStyles, 
			const RECT& rect, CWnd* pParentWnd)
		{
			static char BASED_CODE szMyClass[] = "MYCLASS";
			return CWnd::Create(szMyClass, lpszWindowName,
				dwStyles, rect, pParentWnd);
		}

	// add additional member functions to support custome WM_
	// SendMessages here


	DECLARE_MESSAGE_MAP() // use this to handle messages as
				// you would expect
};

You don't even need to derive your own class if you don't plan
on customizing the Window at all, since CWnd::Create will
allow you to pass a Window class name.  The window will still then be
part of the normal MFC message routing.	
			
>
>        2. In processing WM_PAINT, BeginPaint() API is called
>           and an invalidated region of the window is returned.
>           What about WM_NCPAINT?  Is there a way to detect only
>           the invalidated area in the non-client area for
>           painting?  Or do I have to paint the entire non-client
>           area everytime?
>
>    Thanks in advance.

Painting in the non-client area of a Window is "not recommended" (from
page 475 of the Programmers Reference v2).  If you must, then
you retrieve a DC via CWnd::GetWindowDC.  In your code you should
paint everything.


-- 
Steven Sinofsky
stevesi@microsoft.com
Disclaimer: I don't speak for Microsoft, BillG does that.