如何从cloudkit下载多个记录

Question

我想从云套件下载多个项目，但我得到的错误“无法指定类型值（CKQueryCursor！，NSError） - >（）键入（CKQueryCursor ?, NSError？ ） - > void“

let locationToLookFor = CLLocation() 
let predicate = NSPredicate(format: "location = %@", locationToLookFor as CLLocation) 
let query = CKQuery(recordType: "Location", predicate: predicate) 
let operation = CKQueryOperation(query: query) 
operation.recordFetchedBlock = self.recordFetchBlock 
operation.queryCompletionBlock = 
{ 
    [weak self] 
    (cursor: CKQueryCursor!, error: NSError) in 
    if(cursor != nil) 
    { 
     print("Fetching records") 
     let newOperation = CKQueryOperation(cursor: cursor) 
     operation.recordFetchedBlock = recordFetchBlock 
     operation.queryCompletionBlock = operation.queryCompletionBlock 
     self!.operationQueue.addOperation(newOperation) 
    } 
    else { 
     print("We have fetched all data") 
    } 
} 
operationQueue.addOperation(operation) 

Answer 1

您的结案签名与所需签名不匹配。如错误消息所示，cursor应该是可选的，应该是error。你也会得到一个错误，因为当你将它提供给新的操作时你不打开cursor。

尝试：

operation.queryCompletionBlock = 
{ 
    [weak self] 
    (cursor: CKQueryCursor?, error: NSError?) -> Void in 
    if let cursor = cursor 
    { 
     print("Fetching records") 
     let newOperation = CKQueryOperation(cursor: cursor) 
     operation.recordFetchedBlock = recordFetchBlock 
     operation.queryCompletionBlock = operation.queryCompletionBlock 
     self?.operationQueue.addOperation(newOperation) 
    } 
    else { 
     print("We have fetched all data") 
    } 
}