ios - 如何获取已存在共享的 CKShare 对象(以获取共享 URL)

Question

我试图允许我的应用程序的用户能够检索他们已经共享的记录的 iCloud 共享链接。我可以在创建共享时通过使用 let share = CKShare(rootRecord: CKRecord) 和 Apple 的 UISharingController 来获取 URL。但是，每次我使用此方法时，旧链接都会失效，并将其他人踢出他们已经加入的共享。如何允许用户(记录所有者)随时获取记录 CKShare 对象的可共享 URL？

//Initially shares the record
let share = CKShare(rootRecord: newRecord)
share[CKShare.SystemFieldKey.title] = "Group" as CKRecordValue?        
let modifyRecordsOperation = CKModifyRecordsOperation( recordsToSave: [newRecord, share], recordIDsToDelete: nil)

//Activates the UISharingController (code not shown)

Answer 1

假设记录已共享，您可以通过以下方式获取邀请其他参与者的 URL:

if let shareReference = record.share {
    database.fetch(withRecordID: shareReference.recordID) { (share, error) in
        let shareURL = (share as? CKShare)?.url
    }
}

如果您想再次显示现有共享的 UICloudSharingController(不生成新 URL)，您可以这样做:

let sharingController = UICloudSharingController { (_, prepareCompletionHandler) in

    func createNewShare() {
        let operationQueue = OperationQueue()
        operationQueue.maxConcurrentOperationCount = 1

        let share = CKShare(rootRecord: record)
        share[CKShare.SystemFieldKey.title] = "Title" as CKRecordValue
        share.publicPermission = .readWrite

        let modifyRecordsOp = CKModifyRecordsOperation(recordsToSave: [share, record], recordIDsToDelete: nil)
        modifyRecordsOp.modifyRecordsCompletionBlock = { records, recordIDs, error in
            prepareCompletionHandler(share, self, error)
        }
        modifyRecordsOp.database = database
        operationQueue.addOperation(modifyRecordsOp)
    }

    if let shareReference = record.share {
        database.fetch(withRecordID: shareReference.recordID) { (share, error) in
            guard let share = share as? CKShare else {
                createNewShare()
                return
            }
            prepareCompletionHandler(share, self, nil)
        }
    } else {
        createNewShare()
    }
}