auto_position - Automaticallo locate an instance in a collection

This option is typically set for singular references in order to select the first and only instance in the collection, when existing. One may also set this option for list control data sources in order to select the first instance in the list (collection). Otherwise, no item will be selected in the list.

When the collection is empty, no entry will be selected except, auto-initialization has been requested by setting auto_init. In this case an empty (initialized) instance will be provided and selected in the data source. The instance exists temporarily, only, until something is changed or the instance is stored explicitly.