SetClassLong GCL_CURSOR on custom window

I wrote a function to change the cursor when a user hovers over a certain area of a custom window, however to stop flickering I also set the cursor class of this window to NULL. The problem i'm having now is mIRC is setting EVERY custom window's cursor class to NULL
Here's my code:

Code:

int WINAPI SubWindow(HWND mWnd, HWND aWnd, char *data, char *parms, BOOL show, BOOL nopause)
{
        hTicker = (HWND)atol(data);
	if(IsWindow(hTicker)) 
	{
		SetClassLong(hTicker, GCL_HCURSOR, (LONG)NULL);
                // More unrelated code here
        }
        return 3;
}

Code:

int WINAPI mCursor(HWND mWnd, HWND aWnd, char *data, char *parms, BOOL show, BOOL nopause)
{
	HCURSOR hCurs;
	if (!lstrcmp(data, "Hand"))
		hCurs = LoadCursor(NULL, MAKEINTRESOURCE(32649));
	else if (!lstrcmp(data, "Arrow")) 
		hCurs = LoadCursor(NULL, IDC_ARROW);
	else {
		lstrcpy(data, "E_INVALIDPARAMETERS");
		return 3;
	}
	SetCursor(hCurs);
	lstrcpy(data, "S_OK");
	return 3;
}

Am I doing something wrong? The only thing I can think of is maybe i'm setting the global cursor class for custom windows to NULL instead of just for the one window. Please help

Your assumption is right. You're modifying the Window CLASS (SetClassLong). Take a look at "SetWindowLong" instead, which operates on HWNDs, not their WNDCLASSEX structures.

Oh I get it now, thanks for that. I did look in to SetWindowLong before SetClassLong but couldn't find anything about setting cursors though.

Unless you mean suclassing the window then using SetCursor when my window proc catches WM_MOUSEMOVE?

Thanks again

If it's not available for SetWindowLong then it may not be possible to set on a per-window basis, in which case you would probably need to subclass the window, yes.

So i've been researching this for a few hours now to no avail, if anybody else is interested in this here is the solution I came up with:

Code:

HCURSOR hDefCursor;

case WM_MOUSEMOVE:
{
	if (!bHover)
	{
		bHover = TRUE;
                
                // Set class cursor to NULL when cursor is over the window
		SetClassLong(hwnd, GCL_HCURSOR, (LONG)NULL);


		lstrcpy(mData, "/.signal -n tick_mouse_enter");
		SendMessage(hmIRC, WM_MCOMMAND, 0, 0);

		SetTimer(hwnd, MOUSE_TIMER, 1, NULL);
	}
                // More Unrelated Code
}
break;
case WM_TIMER: 
{
	if ((int)wParam == MOUSE_TIMER)
	{
		GetCursorPos(&pt);
		GetWindowRect(hwnd, &rM);

		if(!PtInRect(&rM, pt))
		{
		    bHover = FALSE;

                    // Set class cursor back to arrow when the cursor leaves the window
		    hDefCursor = LoadCursor(NULL, IDC_ARROW);
		    SetClassLong(hwnd, GCL_HCURSOR, (LONG)hDefCursor);

		    KillTimer(hwnd, MOUSE_TIMER);
	
		    lstrcpy(mData, "/.signal -n tick_mouse_leave");
		    SendMessage(hmIRC, WM_MCOMMAND, 0, 0);
		}
	}
}
break;

Did you try to subclass the window like I suggested?

Yea I did, but I found out Windows restores the class cursor EVERY time there's a WM_MOUSEMOVE message. I think my method is the only way I can stop the flickering. Do you have any other ideas?
Thanks

N.B: http://blogs.msdn.com/oldnewthing/archive/2006/02/27/539880.aspx has some more on it, but nobody there had a great solution either

I'm not quite sure what the disadvantage of reassigning to another window class would be.. I don't think mIRC makes much use of the classes themselves.. I could be wrong.

I wasn't sure you could reassign the window's class after it had been created? I've been doing a bit more research and found out about "superclassing" - seems to be exactly what I need so i'll give that a shot.

EDIT: Ok it seems superclassing is just for creating new windows from an edited class, annoying