static const char * EVENT_UPDATE_VIEWER_BLOCKED = "UpdateViewerBlocked";
static const char * EVENT_UPDATE_VIEWER_UNBLOCKED = "UpdateViewerUnblocked";
+static const char * EVENT_EMPTY_AIS_PRESENTATION = "EmptyAISPresentation";
+static const char * EVENT_EMPTY_OPERATION_PRESENTATION = "EmptyOperationPresentation";
+
static const char * EVENT_PREVIEW_BLOCKED = "PreviewBlocked";
static const char * EVENT_PREVIEW_REQUESTED = "PreviewRequested";