domainIdentifier
An optional identifier that represents the domain or owner of the item.
Declaration
var domainIdentifier: String? { get set }Discussion
Specify a domain identifier to group items together and to make it easy to delete groups of items from the index. For example, you might specify an identifier for a mailbox in an account whose indexed data you want to remove when the account is deleted. In this example, domainIdentifier should be of the form <account-id>.<mailbox-id>, where neither <account-id> nor <mailbox-id> contain periods. To delete all items associated with the specified account and mailbox, you can call deleteSearchableItems(withDomainIdentifiers:completionHandler:) with a domainIdentifier of <account-id>.<mailbox-id>. Or to delete all items associated with all mailboxes in the specified account, you can call deleteSearchableItems(withDomainIdentifiers:completionHandler:) with a domainIdentifier of <account-id>.