WIndows / C++

[Derek Baker]

Looking on the 'net, there seem to be two solutions on the problem of callback and classes:

making the function static

using a global function to pass the parameters on to a class member function

Does anyone have any opinions on which to use?

Thanks in advance

Derek

[Nobody/Anonymous]

I would make the member function static... less sloppy more portable in my opinion...

Zero Valintine

[Derek Baker]

Thanks for the constructive reply Zero, I'd been expecting something like "whichever you like"!

Anyone else?

Derek

[Anonymous]

The problem with static function sis that they cannot access non-static members, which may be a problem. In situations where it is, I have used a static function that takes an instance pointer as a parameter.

e.g.
static void myClass::callback( myClass* instance ) ;

In callback(), member functions and data may be called through the instance parameter.

If you base myClass on a generic base class where callback() is a virtual function. The class registering the callback would therefore only need to know about the base class making the mechanism generic.

[Derek Baker]

To clarify, the callback function that I am referring to in this instance is a windows procedure. Initially, a single main procedure, afterwards a procedure for multiple child windows.

Derek

[Derek Baker]

Update:

I now have it working using a static member function for the WndProc, at least as a single window.

No doubt, more fun ahead as try to make it MDI and introduce multiple child window!

Derek