+/* DrawingArea name used by "{layout}.{area}" */
+static const char *kNameLayoutNormal = "normal";
+static const char *kNameLayoutSplit = "split";
+static const char *kNameAreaFull = "full";
+static const char *kNameAreaMain = "main";
+static const char *kNameAreaSub = "sub";
+
+/* Key for json obejct */
+static const char *kKeyDrawingName = "drawing_name";
+static const char *kKeyDrawingArea = "drawing_area";
+