-#define GDI_CALLBACK 22
-#define GDI_AREA_SIZE 23
-#define GDI_ITEM_SIZE 24
-#define GDI_SCROLLBAR_ITEMS_MAX 25
-#define GDI_SCROLLBAR_ITEMS_VISIBLE 26
-#define GDI_SCROLLBAR_ITEM_POSITION 27
+#define GDI_CALLBACK_INFO 22
+#define GDI_CALLBACK_ACTION 23
+#define GDI_AREA_SIZE 24
+#define GDI_ITEM_SIZE 25
+#define GDI_SCROLLBAR_ITEMS_MAX 26
+#define GDI_SCROLLBAR_ITEMS_VISIBLE 27
+#define GDI_SCROLLBAR_ITEM_POSITION 28
+#define GDI_DESCRIPTION_TEXT 29