swift - 保存和获取 CloudKit 引用

Question

我在使用 CloudKit References 进行创建时遇到问题。数据正在保存到 CloudKit 中，但它没有引用其父级(列表)。不知道我做错了什么，任何帮助将不胜感激!

保存方法

var list: CKRecord?
var item: CKRecord?    

@objc func save() {
    let name = nameTextField.text! as NSString

    //Fetch Private Database
    let privateDatabase = CKContainer.default().privateCloudDatabase

    if item == nil {
        //Create Record
        item = CKRecord(recordType: RecordTypeItems)

        //Initialization Reference
        guard let recordID = list?.recordID else { return }
        let listReference = CKRecord.Reference(recordID: recordID, action: .deleteSelf)

        item?.setObject(listReference, forKey: "list")
    }

    item?.setObject(name, forKey: "name")

    //Save Record
    privateDatabase.save(item!) { (record, error) in
        DispatchQueue.main.sync {
            self.processResponse(record: record, error: error)
        }
    }
}

获取方法

var list: CKRecord!
var items = [CKRecord]()

private func fetchItems() {
    //Fetch Private Database
    let privateDatabase = CKContainer.default().privateCloudDatabase

    //Initialize Query
    guard let recordID = list?.recordID else { return }
    let reference = CKRecord.Reference(recordID: recordID, action: .deleteSelf)
    let query = CKQuery(recordType: RecordTypeItems, predicate: NSPredicate(format: "list == %@", [reference]))


    //Configure Query
    query.sortDescriptors = [NSSortDescriptor(key: "name", ascending: true)]

    //Peform Query
    privateDatabase.perform(query, inZoneWith: nil) { (records, error) in
        DispatchQueue.main.sync {
            self.processResponseForQuery(records: records, error: error)
        }
    }
}

Answer 1

在创建查询来检索引用列表的项目时，谓词格式字符串中的列表引用是否应该位于数组内？如果您创建项目的引用(如 item?.setObject(listReference, forKey: "list"))，CloudKit 会将 list 字段推断为单个 CKRecord。引用，因此查询将是:

let query = CKQuery(recordType: RecordTypeItems, predicate: NSPredicate(format: "list == %@", reference))