2011

When you select all objects in a base class, objects in object classes based
on that class are also selected.
Using Object Classes as Base Classes Only
Sometimes when you create a base class, you intend to use it only as a base
for other object classes and not to create objects in drawings. For example,
you may not want the to use the Roads object class to create roads. You want
people to create roads using the Primary Roads and Secondary Roads classes
that are based on the Roads class. You can specify that an object class can be
used only as a base class.
Editing Base Classes
To edit a definition for an object class, you must have a sample object in the
drawing. However, if you use an object class as a base class only, you will not
have any example objects. For these object classes, you must edit the .xml
definition file directly.
See also:
■
Defining an Object Class (page 119)
■ Setting Up Object Classification (page 116)
NOTE To define an object class, you must have Alter Object Class privileges (page
82).
NOTE Object classification affects drawing objects only. For information about
classification methods for geospatial feature data, see
Overview of Geospatial Data
(page 551)
To base a new object class on an existing class
1 Define the object class (page 120).
2 For Based On, select the object class on which you want to base this new
object class.
The selected properties of the base object class appear in the list.
3 You cannot clear any of the properties of the base object class, but you
can edit the property attributes, including the default and the range of
allowable values.
Setting Up Object Classification | 123