I resolved my access violation problem by including at the begin of wndProc inside Window class, the following code: //____________________________________________________ private dword wndProc(ptr o_hwnd, dword o_msg, ... { asm{ push 0x00000000; push [o_hwnd]; call [user32.getWindowLong]; mov [EBP - 0x04], EAX; }
switch(o_msg){ ... } //____________________________________________________