Thanks Mike, that did it

 Console.WriteLine("Not in list");
                    //Lets add it to the backer
                    fruits.Add(new Fruit(cell.Text));
                    Console.WriteLine("Adding {0} to fruits.", cell.Text);
                    //Refresh the list
                    fruitListUltraDropDown.Rows.Refresh(RefreshRow.ReloadData);
                    //Get out the new index
                    valueList.GetValue(cell.Text, ref index);
                    Console.WriteLine("New index is {0}", index);
                    //Set the key value
                    cell.EditorResolved.Value = valueList.GetValue(index);

Hi,

rumpot said:

fruits.Add(new Fruit(cell.Text));
                    Console.WriteLine("Adding {0} to fruits.", cell.Text);
                    fruitListUltraDropDown.DataSource = null;
                    fruitListUltraDropDown.DataSource = fruits;
                    fruitListUltraDropDown.DataBind();

I imagine you are doing a lot of this just to be on the safe side, but it's mostly redundant. If fruits is an IBindingList, then you don't need to do any of this, the list will update automatically. If fruits is an IList, then you should call fruitListUltraDropDown.Rows.Refresh(ReloadData). You don't need to set the DataSource or call DataBind.

Anyway, that's nothing to do with the question you are asking.

Instead of setting cell.Value, try setting cell.EditorResolved.Value and see if that works. I think it will. If not, another thing to try would be to get the TextBox from the grid.Controls collection and set it's Text to the DisplayText of the new item.

This fails the first time through, but for all additional adds it works

 Console.WriteLine("NOt in list");
                    //Lets add it to the backer
                    fruits.Add(new Fruit(cell.Text));
                    Console.WriteLine("Adding {0} to fruits.", cell.Text);
                    fruitListUltraDropDown.DataSource = null;
                    fruitListUltraDropDown.DataSource = fruits;
                    fruitListUltraDropDown.DataBind();
                    //SGet out the new index
                    valueList.GetValue(cell.Text, ref index);
                   
                    Console.WriteLine("New index is {0}", index);

//index is always -1 after the first add, 2nd and beyond retreives the proper index
                    //var newValue = valueList.GetValue(index);
                    //Console.WriteLine("NewValue {0)", newValue);
                    cell.Value = valueList.GetValue(cell.Text, ref index);

Thanks Mike, almost there now, I could not use BeforeCellUpdate as it would always throw the exception before that would fire. Now I am unsure how to set the value of cell's dropdown index to the newly added item

 /// <summary>
        /// Handles the BeforeExitEditMode event of the ultraGrid2 control.  All our work should go here to add to the list
        /// </summary>
        /// <param name="sender">The source of the event.</param>
        /// <param name="e">The <see cref="Infragistics.Win.UltraWinGrid.BeforeExitEditModeEventArgs"/> instance containing the event data.</param>
        private void ultraGrid2_BeforeExitEditMode(object sender, Infragistics.Win.UltraWinGrid.BeforeExitEditModeEventArgs e)
        {
            Console.WriteLine("ultraGrid2_BeforeExitEditMode: sender {0}", sender);
          
            UltraGrid grid = sender as UltraGrid;
            //What cell raised this event?
            var cell = grid.ActiveCell;
            if (cell.Column.Index == 1)//This is the fruit ID
            {
               //Cast to the IValueList
                IValueList valueList = cell.ValueListResolved;
                int index = 0;
                if (valueList.GetValue(cell.Text, ref index) != null)
                {
                    Console.WriteLine("Already in list, nothing to do");
                }
                else
                {
                    Console.WriteLine("NOt in list");
                    //Lets add it to the backer
                    fruits.Add(new Fruit(cell.Text));
                    Console.WriteLine("Adding {0} to fruits.", cell.Text);
                    fruitListUltraDropDown.DataSource = null;
                    fruitListUltraDropDown.DataSource = fruits;
                    fruitListUltraDropDown.DataBind();
                    //How to set it to the newly added item in the value list
                }
            }
        }

It still throws an exception cannot convert "grape" to int.32. The datasource/Valuelist contain the new value but I am unsure how to set the cells valueListiIndex to the new item I just added.

Regards

_Eric