Description: Runs the lookup ComboBox's default formula when its visible selection changes.
Execution: On desktop, the ComboBox change handler executes the formula directly while the DBForm is in Ready state. At that point the new selection has not yet been written to EntryData.CurValue, so the connected entry variable in the DBForm parser can still contain its previous value.
Initialization: Entering input mode calls the same change handler once after connecting it. Therefore the formula can run without a user selection change when the DBForm is already Ready.
Write-back note: When the drop-down closes, the component writes the new value directly to EntryData.CurValue before calling UpdateValue. That call normally sees no difference, so it may skip the usual Changed state and RunChangeEvents path. The latter would only recalculate and would not execute this formula again.
Arguments: There are no event-specific arguments. The direct script call does not populate the common event arguments and does not expose the new selection separately.
Result: Any value assigned to Result is ignored. Formula side effects are retained after successful calculation.
Availability: Desktop only. The web factory branch for LuComboBox is disabled, so no web component or event is created.
Example: Avoid depending on the connected entry as the new selection in this event.
ShowMessage("The lookup ComboBox selection changed");