Hi doyouknowme,

This behavior is certainly possible; you would need to handle the KeyDown event of the XamMultiColumnComboEditor instance(s) in question, while checking for the Tab key, next you would need to select the first item in the items collection via the SelectedIndex property.

Also, assuming that you want to also override the original tab behavior and give the appearance that the drop down never opened for this process, you could also handle the keydown before its processed outside of the control’s context and ensure that its IsDropDownOpen property ensures a closed state.

I have included the following code snippet for further context as well as the attached sample which I have constructed for this issue.

		private void xamMultiColumnComboEditor1_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.Key == Key.Tab)
            {
                xamMultiColumnComboEditor1.SelectedIndex = 0;
 
                e.Handled = true;
 
                xamMultiColumnComboEditor1.IsDropDownOpen = false;
            }
        }

Sincerely,
Chris K
Developer Support Engineer
Infragistics, Inc.
www.infragistics.com/support