Hi Terry,
The only thing that bothers me with your layout is that it seems you haven't thought it through yet, I mean you don't have definite designated roles for levels 2 and 3 - I think that once you've decided that, you would have less trouble deciding what class to use as parent class

For example one possible way to look at your level layout can be
level1 - is the FFC class
level2 - is just a subclass of the FFC class so that if you change any FFC behavior you won't have a problem when there's a new version of the FFC classes
level3 - specialized sub-classes from level2 classes (i.e. classes with tie-ins to your framework etc.)

thus a new class would be subclasses off of level 2 if it doesn't need any of the extra functionality of level3 or off of level 3 if it does.

Arnon



>Hello Arnon,
>
>My level1 library is _base.vcx the subclassing of VFP subclasses. Level2 is a subclassing of everything in level1 with some added ActiveX controls and composite controls. Level3 is to level2 what level2 is to level1. I though this was a common structure that many used according to devcon seminars. Because the idea is to have each control represented on each level I hate to delete one. If I want a new level3 class that is a subclass of the custom control I could base it on a parent in level3 or level2. I guess it depends whether I want level3's custom control to vary without affecting my new control or not. Do you see my concern about creating a class hierarchy in a way that I won't have to go back and redefine tons of stuff because I did it the wrong way all along?
>Thanks for your last response.
>