I often use UltraDropDown with UltraWinGrid and it work fine.

I add Order_Id to my table PurchaseDetail and I do not get my drop down list. 

I searched and I did not find out why ?

Do you can help me to find why is the ValueMember is appear and not the DisplayMember and I don't have my drop down list.

Many other place I use the same code and procedure and work fine.

All data was perfect load on uddOrder.DataSource

Some code : 

uddOrder.DataSource = PBL.GetList(a => !a.IsInactive);

ugrdPurchaseDetail.DisplayLayout.Bands[0].Columns["Order_Id"].ValueList = uddOrder;

uddOrder.DisplayMember = "IdNumber";
uddOrder.ValueMember = "Id";

band.Columns["Order_Id"].Style = ColumnStyle.DropDownList;

Francois