Queries the item at position item_index in model for the link specified by link.
If the link exists, the linked #GMenuModel is returned. If the link does not exist, null is returned.
the index of the item
the link to query
the linked #GMenuModel, or null
Queries the item at position item_index in model for the link specified by link.
If the link exists, the linked #GMenuModel is returned. If the link does not exist, null is returned.