TextBox and ListBox relationship within Form

[ponymc]

I have spent a while searching for similar examples to my problem and as yet I have found none

I have a simple form with a TextBox and a MoveList ListBox.
The TextBox looks up a list of Suppliers. These Suppliers are found in a Table V2_SupplierMain and have a unique identifier field called internalSupplierID. The field that I have added to my new form (frm = V2_SupplierMatGroup) is the Supplier.Name field.

The ListBox has a Standard 'Available' and 'Selected' look and feel to it and looks up a Table of Material Groups.

The basic premise behind the Form is that I should be able to select a Supplier (there are 235 in the list) and the ListBox should show if any MaterialGroup( there are approx 115) has been selected. If need be I can either move over any new Material Groups to the Selected box or move them back to the Available box.

From here I can then query a list of Suppliers with MaterialGroups mapped.

Problem is I don’t seem to be able to successfully associate my Supplier TextBox with the ListBox so that when you click on different Suppliers it remembers which MaterialGroups you associated with it.

Maybe the design concept is incorrect

Any suggestions would be gladly accepted