Add inventory dimensions

I have created new customized table with item id and invent dim id, I have added this two fields in the customized new form in the grid section.
I have added my customized table and invendim as datasource. I have added “invendimension” datagroup for invent dim selection. In the inventdim section. It is not loading variants based on the selected item. For example, configuration section should display based on the selected item.
Please guide me.