You can just call them in your code, in this respect, /you/ are the 'FieldsDefs-Editor'
I know how to write code to manipulate Fielddefs.
But i don't want to reinvent a working editor. "It's not broken -- i don't want to fix it". I want to use it instead.
The Question is how to use this wellknown editor in a runtime application.
At least in which unit i can find it.