Hierarchical Property Values
Instead of having the property value selection field show a flat list of values, you can set it to show a hierarchically ordered list, which can be built either on top of value lists or real object types. This section explains how you can set up the property value selection field to show an object type based hierarchy. If you would like to specify and use hierarchical value lists instead, see Value list hierarchy.
Before you can set a hierarchy to be used by a property, you of course must have one available to you. See the example in Creating an Object-Based Hierarchy to get started. After you have finished creating the hierarchy, you can put it to use as explained in Specifying Hierarchical Properties.