HKDeletedObject

Use HKAnchoredObjectQuery queries to generate a list of recently deleted objects. Create a query using the init(type:predicate:anchor:limit:resultsHandler:)method. When the system calls the result handler, it passes the deletedObject parameter an array of HKDeletedObject instances matching the query.

Deleted objects are temporary; the system may remove them from the HealthKit store at any time to free up space. To guarantee that you receive notifications for all deleted objects, create an HKObserverQuery and register it for background delivery. The system then wakes your app and calls the observer query’s update handler whenever the matching objects change—including deletions. However, the query does not provide a list of deleted objects. To determine which objects were deleted, use the observer query’s update handler to create an anchored object query for the newly deleted objects.