Release 10.1A: OpenEdge Development:
Progress Dynamics Advanced Development

Customizing classes for some objects

To customize classes for a group of specific objects, you extend a class by creating a new class. This is called subclassing or extending off the bottom, because in Progress Dynamics, the classes that contain objects are typically bottom classes that have no child or descendent classes.

For example, the DynView class is a bottom-level class, and you can create your own class by extending the DynView class to include specific custom attributes. From this customized class, you could then create custom dynamic viewers that would inherit the behavior of the DynView class as well as the custom behavior and attributes that you add.

If you created a subclass named the FilterView class, and made this class a subclass of the bottom level DynView class, you can use the subclass to provide specific behavior for a specific group of objects. You could then create custom dynamic viewers that would inherit the behavior of the FilterView class.

The following sections provide information about extending a class for a group of objects. When you customize classes from the bottom, the customization only applies to the specific objects that you create from this customized class.

Note: Customizing classes from the bottom does not impact the standard objects that come with Progress Dynamics

After you add new attributes and extend the Object type hierarchy, you must restart your session.