The framework calls this member function to inform an application's main window procedure that a modal dialog box or a menu is entering an idle state.
Specifies whether the message is the result of a dialog box or a menu being displayed. This parameter can be one of the following values:
MSGF_DIALOGBOX The system is idle because a dialog box is being displayed.
MSGF_MENU The system is idle because a menu is being displayed.
Specifies a pointer to the dialog box (if nWhy is MSGF_DIALOGBOX), or the window that contains the displayed menu (if nWhy is MSGF_MENU). This pointer may be temporary and should not be stored for later use.
A modal dialog box or menu enters an idle state when no messages are waiting in its queue after it has processed one or more previous messages.
This member function is called by the framework to allow your application to handle a Windows message. The parameters passed to your function reflect the parameters received by the framework when the message was received. If you call the base-class implementation of this function, that implementation will use the parameters originally passed with the message and not the parameters you supply to the function.