/// <summary> /// Controls call this to enter menu mode. ///</summary> public void PushMenuMode(PresentationSource menuSite) { if (menuSite == null) { throw new ArgumentNullException("menuSite"); } menuSite.VerifyAccess(); menuSite.PushMenuMode(); _menuModeCount += 1; if (1 == _menuModeCount) { EventHandler enterMenuMode = EnterMenuMode; if (null != enterMenuMode) { enterMenuMode(null, EventArgs.Empty); } } }