In a Tree-View control, each item in the hierarchical list is identified by an ID that is assigned at the time the element is added to the control. This provides a unique way to identify each item and thus allows for duplicate items at different points in the hierarchy without any confusion. Tree-View ID's are declared in COBOL as USAGE POINTER data items.
Tree-View controls have a variety of special properties, including the ability to store hidden data with any item and to display bitmaps adjacent to the items. The special property called ITEM is used to identify which item in the hierarchy is to be affected by the property values you provide. Typically, you set the value of the ITEM property to the ID of the item to be acted on, and then you set another property (such as ITEM-TEXT or ENSURE-VISIBLE or HAS-CHILDREN or BITMAP-NUMBER) to assign a value or setting to that item. Note that you must set the value of ITEM before you set the other property value in order to get the desired results. ITEM is the "index" for the Tree-View control (see the MODIFY and INQUIRE statements for a description of indexes).