middle button so a portable application should avoid relying on the events from
it.
+For the \texttt{wxEVT\_ENTER\_WINDOW} and \texttt{wxEVT\_LEAVE\_WINDOW} events
+purposes, the mouse is considered to be inside the window if it is in the
+window client area and not inside one of its children. In other words, the
+parent window receives \texttt{wxEVT\_LEAVE\_WINDOW} event not only when the
+mouse leaves the window entirely but also when it enters one of its children.
+
{\bf NB:} Note that under Windows CE mouse enter and leave events are not natively supported
by the system but are generated by wxWidgets itself. This has several
drawbacks: the LEAVE\_WINDOW event might be received some time after the mouse