The configuration data for push notifications sent by the subscription.
- iOS 8.0+
- macOS 10.10+
- UIKit for Mac 13.0+Beta
- tvOS 9.0+
- watchOS 6.0+Beta
If you want your subscription’s push notifications to alert the user to corresponding changes, assign a value to this property. The server uses the information in the
CKSubscription object to determine the delivery options for notifications. For example, you can specify the alert text to display and the name of a special sound file to play. When a push notification involves a record, you can also specify which fields of the record to include in the push notification’s payload data.
If you do not assign a value to this property, the server still sends push notifications to your app but those notifications do not cause the system to alert the user. The default value of this property is