iphone - 当被管理对象出现故障时，如何正确处理KVO通知？

Question

来自docs :

When Core Data turns an object into a fault, key-value observing (KVO) change notifications (see Key-Value Observing Programming Guide) are sent for the object’s properties. If you are observing properties of an object that is turned into a fault and the fault is subsequently realized, you receive change notifications for properties whose values have not in fact changed.

那么，如果一个对象出现故障，Core Data 是否会针对更改的属性发送 KVO 通知？因此，在对通知感到满意之前，我必须始终检查 isFault == NO 吗？

Answer 1

isFault 不可靠，因为发送 KVO 通知时 isFault 可能仍返回 NO。人们应该检查 faultingState 来了解这一点:

faultingState Returns a value that indicates the faulting state of the receiver.

• (NSUInteger)faultingState Return Value 0 if the object is fully initialized as a managed object and not transitioning to or from another state, otherwise some other value.

Discussion The method allow you to determine if an object is in a transitional phase when receiving a key-value observing change notification.