Release 10.1A: OpenEdge Development:
Progress Dynamics Basic Development

Subclassing dynamic combos and lookups

Beginning in Progress Dynamics Version 2.1B, the underlying class structure of combos and lookups changed. The change supports the performance enhancements and new client data caching scheme. (See the chapter in OpenEdge Development: Progress Dynamics Advanced Development about the client data cache and caching of dynamic combos and lookups.) The old class structure had Field as the parent class and DynCombo and DynLookup as children. The new class structure inserts a new parent class called LookupField between Field and DynCombo and DynLookup.

The normal way to create custom subclasses here would have been to subclass DynCombo or DynLookup. If you did this, the new class structure should not affect your code. In the future, you should continue to subclass DynCombo and DynLookup. LookupField should not be subclassed.