Matrix

I had added column in system matrix.. for that i had to set cfl.. this is my code

Dim objStatus1 As SAPbouiCOM.Matrix
            Dim mat As SAPbouiCOM.Matrix = objFrm.Items.Item("38").Specific
            Try
                'objStatus = objFrm.Items.Add("txtWHouse", SAPbouiCOM.BoFormItemTypes.it_EDIT)
                objStatus1 = mat.Columns.Item("U_ConvNo").Cells.Item(0).Specific.value
                Dim txtStatus1 As SAPbouiCOM.Matrix = objStatus1.Specific
                txtStatus1.DataBind.SetBound(True, "", "U_ConvNo")

                Dim cflparam1 As SAPbouiCOM.ChooseFromListCreationParams = objApp.CreateObject(SAPbouiCOM.BoCreatableObjectType.cot_ChooseFromListCreationParams)
                Dim txt1 As SAPbouiCOM.Matrix = objStatus1.Specific
                cflparam1.UniqueID = "TabCfl"
                cflparam1.ObjectType = "64"
                cflparam1.MultiSelection = False
                objFrm.ChooseFromLists.Add(cflparam1)
                txt1.ChooseFromListUID = "TabCfl"
                txt1.ChooseFromListAlias = "WhsCode"
            Catch ex As Exception
            End Try

but its not working.....?