registerCloudKitShare(preparationHandler:)
Registers a handler that prepares a new CloudKit share.
Declaration
func registerCloudKitShare(preparationHandler: @escaping (@escaping (CKShare?, CKContainer?, (any Error)?) -> Void) -> Void)Parameters
- preparationHandler:
The handler the service invokes when it requires the CloudKit share.
Discussion
Use this method to share a hierarchy of CloudKit records with other iCloud users. When the service invokes the handler, create an instance of CKShare with a root record. Save the share to the server using CKModifyRecordsOperation. The root record (and its hierarchy) must already exist on the server or be part of the same save operation. After the share saves, call preparationCompletionHandler with the saved share and its container. If the save fails, pass the error to the completion handler instead. Invoking the sharing service with a share you register using this method prompts the user to begin sharing.
Use the NSCloudSharingServiceDelegate protocol to respond to any changes the sharing service makes.
The following example shows how to create an item provider with a handler that saves a share. It then invokes the cloud-sharing service with that provider.
func beginSharing(_ record: CKRecord) {
let itemProvider = NSItemProvider()
// Register a handler that creates a CloudKit share using
// the provided record, and saves them both to the server
// before passing them to the sharing service.
itemProvider.registerCloudKitShare(preparationHandler: { completion in
let container = CKContainer.default()
// Create a share and use the record the caller provides as
// its root record.
let share = CKShare(rootRecord: record)
// Create an operation that saves both the record and the
// share to CloudKit.
let records = [record, share]
let operation = CKModifyRecordsOperation(recordsToSave: records,
recordIDsToDelete: nil)
// If the save fails, pass the error to the completion handler.
// Otherwise, pass the new share and its container.
operation.modifyRecordsCompletionBlock = { _, _, error in
if let error = error {
completion(nil, nil, error)
} else {
completion(share, container, nil)
}
}
// Set an appropriate QoS and add the operation to the
// container's queue to execute it.
operation.qualityOfService = .userInitiated
container.privateCloudDatabase.add(operation)
})
let items = [itemProvider]
// Create a cloud-sharing service and invoke it to begin sharing.
if let service = NSSharingService(named: .cloudSharing),
service.canPerform(withItems: items) {
service.perform(withItems: items)
}
}