Re: Button class

Hi there!!

I'm new in this forum so i want to say "hi" to everyone.

Well, here ti comes my problem:

I'm writing a simple application based in a code from a book
(programming in C++ for windows of Anthony Porter) without any MFC code
and Compiling in VC++ 6.0.

The app have a simple WS_OVERLAPPED window and inside a button. The
code uses the Win32 API functions "SetProp" an "GetProp" to store the
handler of the window and the button.

The button stores a pointer in the window class to the procedure to do
when the button is pressed (Window::*ClickCallBack)(Window), to call it
later (Window->*ClickCallback)

Inside the custom MessageProc callback function, after the WM_COMMAND,
the window calls a GetProp to point to the button and call the function
mentioned above.

Well, everything good at this point. when i run the program it displays
an Exception. The problem is that the SetProp function don't store the
handle to the button correctly, but the it dows with the window.

The way to use the functions is this:
SetProp(hWnd,(LPSTR)MAKELONG(aProp,0),(HANDLE)this);
              ^ ^ ^
            |the poiner to | | An atom | the
            |the button or WIndow | | specified | Button or
window

(Buton*)(void*)GetProp(hWnd,(LPSTR)MAKELONG(aProp,0));
                                    ^
                               Pointer from
                           the LOPARAM(lParam)
                                 value

Please help me!! What's wrong?
If it's a little messy, i will bring the source code....
( Sorry for my english, i'm a spanish-speaker )