问题描述
我的用例如下:
我的应用程序的每个用户都可以作为所有者创建一组项目。
这些项目是私有的,直到所有者邀请其他用户作为参与者共享所有项目。
参与者可以修改共享项目和/或添加其他项目。
因此,共享不是与单个项目相关,而是与所有者的所有项目相关。
我想使用 CoreData 和 CloudKit 来做 CoreData/CloudKit 镜像并拥有私有和共享项目的本地副本。 根据我的理解,CoreData 和 CloudKit 将所有镜像项放在一个特殊区域“com.apple.coredata.cloudkit.zone”的私有数据库中。 因此,该区域应该是共享的,即其中的所有项目。
在 WWDC 2021 视频 „Build apps that share data through CloudKit and Core Data“ 中,据说 NSPersistentCloudKitContainer
可选地使用记录区域共享,而不是使用根记录进行分层记录共享。
在 the docs 到 UICloudSharingController
中,给出了如何使用 rootRecord
共享记录的示例。
我认为这可以修改为使用共享记录区域。shareRecord
例如可以用
let shareRecord = ckshare(rootRecord: rootRecord)
与
let shareRecord = ckshare.init(recordZoneID:)
但这是否是使用 Apple 进行镜像的记录区域的 ID,即“com.apple.coredata.cloudkit.zone”?如果是这样,如果我只有区域名称,我如何获得它的 CKRecordZone.ID
?
解决方法
现在我想出了如何做到这一点。也许它可以帮助其他人。
首先点击分享按钮。
首先,检查 iCloud 私有数据库中是否已存在 CKShare
记录。
根据它,UICloudSharingController
被初始化以创建它或使用它。
如果它应该创建共享,则进行相应的配置。
// See <https://developer.apple.com/documentation/uikit/uicloudsharingcontroller>
@IBAction func sharingButtonTapped(_ sender: UIBarButtonItem) {
let barButtonItem = sender
/*
If no CKShare record has been stored yet in iCloud,it will be created below using UICloudSharingController initialized with a preparation handler.
If it exists already,UICloudSharingController is initializes with the existing CKShare record.
*/
getShareRecord { result in
DispatchQueue.main.async {
let cloudSharingController: UICloudSharingController!
switch result {
case .success(let ckShareRecord):
if let shareRecord = ckShareRecord {
cloudSharingController = UICloudSharingController.init(share: shareRecord,container: CKContainer.default())
} else {
cloudSharingController = UICloudSharingController { [weak self] (controller,completion: @escaping (CKShare?,CKContainer?,Error?) -> Void) in
guard let `self` = self else { return }
self.share(completion: completion)
}
}
cloudSharingController.delegate = self
if let popover = cloudSharingController.popoverPresentationController {
popover.barButtonItem = barButtonItem
}
self.present(cloudSharingController,animated: true) {}
case .failure(let error):
fatalError("\(error)")
}
}
}
}
// For sharing see https://developer.apple.com/documentation/cloudkit/shared_records
private func share(completion: @escaping (CKShare?,Error?) -> Void) {
if #available(iOS 15,*) {
// iOS 15++
let recordZoneID = CKRecordZone.ID(zoneName: "com.apple.coredata.cloudkit.zone",ownerName: CKCurrentUserDefaultName)
let shareRecord = CKShare(recordZoneID: recordZoneID)
// Configure the share so the system displays the shopping lists name and logo
// when the user initiates sharing or accepts an invitation to participate.
CloudKitHelper.fullNameOfICloudAccount { result in
var fullName: String!
switch result {
case .success(let name):
fullName = name
case .failure(let error):
print("Could not read user name: \(error)")
fullName = "Unknown user"
}
shareRecord[CKShare.SystemFieldKey.title] = String(format: NSLocalizedString("SHARING_LIST_OF_USER",comment:" "),fullName)
let image = UIImage(named: kFileNameLogo)!.pngData()
shareRecord[CKShare.SystemFieldKey.thumbnailImageData] = image
// Include a custom UTI that describes the share's content.
shareRecord[CKShare.SystemFieldKey.shareType] = "com.zeh4soft.ShopEasy.shoppingList"
let recordsToSave = [shareRecord]
let container = CKContainer.default()
let privateDatabase = container.privateCloudDatabase
let operation = CKModifyRecordsOperation(recordsToSave: recordsToSave,recordIDsToDelete: nil)
operation.perRecordProgressBlock = { (record,progress) in
if progress < 1.0 {
print("CloudKit error: Could not save record completely")
}
}
operation.modifyRecordsResultBlock = { result in
switch result {
case .success:
completion(shareRecord,container,nil)
case .failure(let error):
completion(nil,nil,error)
}
}
privateDatabase.add(operation)
}
} else {
// iOS <15
fatalError("Sharing is only available in iOS 15")
}
}
func getShareRecord(completion: @escaping (Result<CKShare?,Error>) -> Void) {
let query = CKQuery(recordType: "cloudkit.share",predicate: NSPredicate(value: true))
privateDB.fetch(withQuery: query) { result in
switch result {
case .success(let returned):
// .success((matchResults: [CKRecord.ID : Result<CKRecord,Error>],queryCursor: CKQueryOperation.Cursor?))
let matchResults = returned.0 // [CKRecord.ID : Result<CKRecord,Error>]
switch matchResults.count {
case 0:
completion(.success(nil))
return
case 1:
let recordResult = matchResults.values.first!
switch recordResult {
case .success(let ckRecord):
completion(.success(ckRecord as? CKShare))
return
case .failure(let error):
completion(.failure(error))
return
}
default:
fatalError("More than 1 CKShare record")
}
case .failure(let error):
completion(.failure(error))
return
}
}
}