Making a mouse hover button, API style

I am trying to make a mouse hoverbutton, API style

- - when mouse is NOT over the button, it stays as it's default image
- when mouse is over the button, it changes to "mouse over image"
- when mouse leaves the button, it changes back to it's default image

here's what i have done so far:
in my main window proc

Code:

---

LRESULT CALLBACK WndProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam)
{
        switch(Message)
        {
                case WM_CREATE:
                        {
                                       
                                dia_hwnd = CreateDialog(GetModuleHandle(0),MAKEINTRESOURCE(IDD_MENU) ,hwnd,MenuProc);
                                ShowWindow(dia_hwnd, SW_SHOWNORMAL);
                                                       
                        TRACKMOUSEEVENT mouse_event_struct;
                        mouse_event_struct.cbSize = sizeof(TRACKMOUSEEVENT);
                        mouse_event_struct.dwFlags = TME_HOVER
                        mouse_event_struct.hwndTrack =dia_hwnd;
                        mouse_event_struct.dwHoverTime = 400;
                        _TrackMouseEvent(&mouse_event_struct);
                       
                       




                                               
                               
                        }
                break;

                case WM_COMMAND:
                        switch(LOWORD(wParam))
                        { ............

---

In my MenuProc proc ( for the window dia_hwnd)

Code:

---

BOOL CALLBACK MenuProc(HWND hwnd, UINT Message, WPARAM wParam, LPARAM lParam)
{
    switch(Message)
    {
        case WM_INITDIALOG:
                        {


                        }
                        break;
        return TRUE;
               
                case WM_MOUSEHOVER:
                        {
                                MessageBox(NULL, "mouse left in", "GOOD",
                        MB_ICONEXCLAMATION | MB_OK);
                        }
                        break;





        case WM_COMMAND:
            switch(LOWORD(wParam))
                                    {........

---

"mouse left in" message never comes up after i moved my mouse into dia_hwnd window
that means that the code doesnt detect that mouse went into the window. There's something wrong here, please help.


using
- win98se
- vc++6.0
- API style

From MSDN:

Quote:

---

The mouse hovered over the client area of the window for the period of time specified in a prior call to TrackMouseEvent. Hover tracking stops when this message is generated. The application must call TrackMouseEvent again if it requires further tracking of mouse hover behavior.

---

You need to call TrackMouseEvent every time you want to recieve the WM_MOUSEHOVER message (if you have already recieved one). I am not actually sure why you don't get one after it has been called in WM_CREATE, although I am sure if I thought about long enough I could come up with something, but that is the same behaviour that I observe.

I recently needed this to and I placed the call to TrackMouseEvent in a WM_LBUTTONDOWN message handler, so I could trigger the message by left clicking on the window. Worked fine, but that is probably not going to suffice for your purposes..