Hi Guys,
I had the same problem with the RadComboBox not showing the EmptyMessage when the AllowCustomText is set to False. I was not satisfied with the solution that was given in this forum which kind of disables the user from typing any value in the combobox (MarkFirstMatch does not work). So, I tried this solution and it seems to work for me.
The aspx code looks like this
The RadComboBox will have the first item as the EmptyMessage Text (In this case it will be "Pick"). This empty message text item will not show on the list of items to pick from the combo box, since it is made hidden on the OnClientDropDownOpening javascript event. If no element is picked from the combo dropdown, then the empty message text item will again show up on the combobox using the OnClientBlur event. The "rcbEmptyMessage" class will give the empty message text item the kind of inline data feel to the combobox (rcbEmptyMessage is the class used by Telerik to show empty message text)
For instances where you need to bind the RadComboBox with a datasource, you can add the first element to combobox in the server side OnDataBound event like this
The javascript needed to do this