Problem with classes

[ChimpFace9000]

Im still learning classes, so could someone please tell me why i get this error...

Error E2235 wndmain.cpp 14: Member function must be called or its address taken in function wndmain::wndmain()

Heres the files...

wndmain.cpp

#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include "wndmain.h"

wndmain::wndmain()
{
	WNDCLASSEX WndClassEx;

	hIconMain	= LoadIcon(NULL, IDI_APPLICATION);
	hCursorArrow	= LoadCursor(NULL, IDC_ARROW);

	WndClassEx.cbSize	= sizeof(WNDCLASSEX);
	WndClassEx.lpfnWndProc	= WndProc;
	WndClassEx.style	= CS_HREDRAW | CS_VREDRAW;

	return;
}

wndmain::~wndmain()
{
	DestroyIcon(hIconMain);
	DestroyCursor(hCursorArrow);

	return;
}

LRESULT	CALLBACK wndmain::WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
	return(0);
}

wndmain.h

class wndmain
{
public:
		wndmain();
		~wndmain();

protected:
	LRESULT	CALLBACK WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam);

	static HICON	hIconMain;
	static HCURSOR	hCursorArrow;
};

The error is with this line in wndmain.cpp...

WndClassEx.lpfnWndProc	= WndProc;

Anything would be helpful.

[kedaman]

2 solutions:

1. make the callback function static and virtually inherit the class to extend it.
2. don't contain the function, in other words have a function pointer.

[ChimpFace9000]

How do i do either of those?

[kedaman]

1. add static and virtual specifiers to the declaration of the callback, then derive a class using virtual functions
2. add a member specifying the function pointer to a LRESULT CALLBACK (*proc)(HWND, UINT , WPARAM , LPARAM ); and use it for WNDCLASSEX. you could initialize this to a default proc in the constructor or have it passed there, or/and use accessors.

[ChimpFace9000]

I spent the last little while trying to do either of those, and i realized, i have no idea what to do. I have a pretty good understanding of c and c++, just not when it comes to pointers and inheritance (dont even know what that is). Could you show an example please. Thanks.

[kedaman]

Inheritance is a very very important concept in object oriented programming, if you learn it now, you'll have benefit of it the rest of your life, have a look at Sam's teach yourself C++ in 21 days and pick up what you missed.