Add inventory dimensions button a form - need help


   I am trying to add selected inventory dimension columns to a form that I am working on. I have added the Inventory dimensions button and the button opens the little dialogue window where I can select the dimensions that I am interested in. But after clicking Ok on the dimensions dialogues window my parent form doesn't display the selected dimensions. I am not sure what I am missing.

Here is my code:

1) in the class declaration of the form I have this variable declared  InventDimCtrl_Frm_EditDimensions    inventDimFormSetup;

2) I have created the inventDimSetUpObject(), updateDesing() in the form methods

3) I added the line   element.updateDesign(InventDimFormDesignUpdate::Init); in the Form's init() method. 

4). On the InventDim datasource properties I have setup the LinkType to InnverJoin and the join source is my main temp table which is the main data source of the form. 

I am not sure what else I need to do for it to be able to show the selected inventory dimensions columns. Any inputs please?