Win32 WndProc as class member

Question

Is there a way to wrap WndProc as private member?

If I have this:

class Window
{
public:
    Window();
    virtual ~Window();
    void create();

private         


        

Answer 1

Make it static:

static LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);

Answer 2

You should add the static modifier to it.

The reason for this, is that when it's a member function (which I believe is a __thiscall in Visual C++), it's actually just a C function taking this as the first parameter. This would look like this:

LRESULT CALLBACK WndProc(Window& this, HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);

If you make it static, the compiler gets rid of the first Window& this parameter, making it compatible with lpfnWndProc .

Answer 3

Yes, it is possible to include a WndProc as a class member. Furthermore, you can modify other class members from it. The trick is to use two WndProc functions, one of them static.