Yes, I think I know what you mean.
I just don't really understand how your own class communicates with the feeder class. Somehow you have to pass the value of the technical fields to the feeder class, don't you? I mean, for example you have a table or a structure with the fields MATNR and the corresponding technical field MATNR_VIS for the visibility of the field MATNR. You set the technical field to visible or hidden. But how does the feeder class know that the values have changed? Do you call your own class in the feeder class?