Assign a selective list to a property, if the respective column should display a Combobox with all items of the list instead of the value field. The value can then only be selected from the list, but not be edited manually anymore.
# Locate an existing or [[Create_a_new_Selective_List|create a new [[Selective List]]
# Assign the list to the '''SELECTIVELIST''' attribute either by
#* dragging and dropping the list object onto the cell