def OnLeftDown(self, event):
        """
        Handles the ``wx.EVT_LEFT_DOWN`` event for L{RoundButton}.

        :param `event`: a `wx.MouseEvent` event to be processed.
        """

        if not self.IsEnabled() or not self._containsEvent(event):
            return
        
        self._mouseAction = CLICK
        self.CaptureMouse()
        self.Refresh()
        event.Skip()

        Handles the ``wx.EVT_LEFT_DOWN`` event for L{RoundButton}.

        :param `event`: a `wx.MouseEvent` event to be processed.
        
recipes/Python/577951_wxPythDramatic_shaded_3D_buttons_that_look_like_/recipe-577951.py