如何将 CloudKit 记录数据从“TableView-Controller B”传递到“View-Controller C”？

Posted 2023-02-24

【中文标题】如何将 CloudKit 记录数据从“TableView-Controller B”传递到“View-Controller C”？

【英文标题】：How to pass the CloudKit records data from "TableView-Controller B" to "View-Controller C"?

【发布时间】：2017-07-01 20:15:21

【问题描述】：

我已经从我的CloudKit 获得记录数据并成功显示在TableViewController-B，但是我如何将CloudKit's records(strings, images) 传递给下一个ViewController-C？ ps. not tableViewcontroller-C

我的第一个TableViewController-B

import UIKit  
import CloudKit  

class BTableViewControoler: UITableViewController 
       var myclouds:[CKRecord] = []
       var imageCache = NSCache<CKRecordID, NSURL>()
       var recordType: String!

    override func viewDidLoad() 
            super.viewDidLoad()

            recordsFromCloud()
        

func recordsFromCloud() 

    let cloudContainer = CKContainer.default()
     let publicDatabase = cloudContainer.publicCloudDatabase  
        let predicate = NSPredicate(value: true)
        let query = CKQuery(recordType: recordType, predicate: predicate)
        query.sortDescriptors = [NSSortDescriptor(key: "creationDate", ascending: false)]

        let queryOperation = CKQueryOperation(query: query)

        queryOperation.desiredKeys = ["name", "address", "GpNumber"]
        queryOperation.queuePriority = .veryHigh
        queryOperation.resultsLimit = 50
        queryOperation.recordFetchedBlock =  (record) -> Void in
            self.myclouds.append(record)
        

        queryOperation.queryCompletionBlock =  (cursor, error) -> Void in
            if let error = error  print("Failed data - \(error.localizedDescription)")
                 return 
        print("Successfully data")  
        
        publicDatabase.add(queryOperation)     
    //fetchRecords End

    override func numberOfSections(in tableView: UITableView) -> Int 

        return 1
    

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int 

        return myclouds.count
    


    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell 
        let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! MainCell


        let newInFo = myclouds[indexPath.row]

        cell.mainLabel.text = newInFo.object(forKey: "name") as? String
        cell.mainNumber.text = newInFo.object(forKey: "GpNumber") as? String
        cell.mainLocation.text = newInFo.object(forKey: "address") as? String
        cell.mainImage.image = UIImage(named: "photoalbum")

        //get image
        if let imageFileURL = imageCache.object(forKey: myclouds.recordID) 

            if let imageData = try? Data.init(contentsOf: imageFileURL as URL)
                cell.mainImage?.image = UIImage(data: imageData)
                
            else

                let publicDatabase = CKContainer.default().publicCloudDatabase
                let fetchRecordsImageOperation =   CKFetchRecordsOperation(recordIDs: [newInFo.recordID])
                fetchRecordsImageOperation.desiredKeys = ["image"]
                fetchRecordsImageOperation.queuePriority = .veryHigh

                fetchRecordsImageOperation.perRecordCompletionBlock = 
                    (record, recordID, error) -> Void in

                    if let error = error 
                        print("Failed image:\(error.localizedDescription)")
                        return
                    

                    if let newinfoRecord = record 
                        OperationQueue.main.addOperation() 
                    if let image = newinfoRecord.object(forKey: "image") 
                                let imageAsset = image as! CKAsset


                    if let imageData = try? Data.init(contentsOf: imageAsset.fileURL) 
                                    cell.mainImage.image = UIImage(data: imageData)
                                

             self.imageCache.setObject(imageAsset.fileURL as NSURL, forKey: newInFo.recordID)

                            
                         
                    //record end
                  

             publicDatabase.add(fetchRecordsImageOperation)
          //else end

          return cell
          //cell end


//Segue To Next View 
       override func prepare(for segue: UIStoryboardSegue, sender: Any?) 
            if segue.identifier == "showDetailSegue" 
                if let indexPath = tableView.indexPathForSelectedRow 
                   let toDetailVC = segue.destination as! showDetailVC
                        toDetailVC.DisData = newinfo[indexPath.row]       
                

我的 ViewController-C

import UIKit
import CloudKit

class showDetailVC: UIViewController 

    @IBOutlet weak var detailpic: UIImageView!

    @IBOutlet weak var containerView: UIView!

    @IBOutlet weak var nameLabel: UILabel!
    @IBOutlet weak var infoLabel: UILabel!
    @IBOutlet weak var mynumberLabel: UILabel!

    var DisData: CKRecord?
    var getType: String!

    override func viewDidLoad() 
        super.viewDidLoad()

        detailpic.image = UIImage(named: "photoalbum")
        infoLabel.text = DisData?.object(forKey: "address") as? String
        nameLabel.text = DisData?.object(forKey: "name") as? String
        mynumberLable.text = DisData?.object(forKey: "GpNumber") as? String   
    

我使用var DisData 从tableViewController-B 获取CKRecord 但它不适用于DisData?.object(forKey: "name") as? String 的方法 并且图像也无法弄清楚如何显示它。 我应该再次在ViewController-C 中使用UITableViewController-B's func recordsFromCloud 吗？？？或任何其他获得Cloudkit's records的聪明方法，请帮忙。

【参考方案1】：

创建一个名为 selectedRecord 的变量

var selectedRecord: CKRecord!

添加委托方法 didSelectRowatindexPath

func tableView(tableView: UITableView, didDeselectRowAtIndexPath indexPath: IndexPath) 

    selectedRecord = myclouds[indexPath.row]
performSegueWithIdentifier("showDetailSegue", sender: nil)

把prepareforsegue改成这个

 override func prepare(for segue: UIStoryboardSegue, sender: Any?) 
                if segue.identifier == "showDetailSegue" 
                       let toDetailVC = segue.destination as! showDetailVC
                            toDetailVC.DisData = selectedRecord       
                    

在showDetailVC中将DisData的类型从CKRecord?改为CKRecord!

var DisData: CKRecord!

如果你想得到你的钥匙，请声明queryOperation 外面 recordsFromCloud()

然后，在showDetailVC中为Keys创建一个变量

var forKeys: [String]!

然后将以下行添加到prepareforsegue

toDetailVC.forKeys = queryOperation.desiredKeys

【讨论】：

它仍然不工作，没有错误但不显示任何东西，仍在努力。谢谢你的想法

它现在正在工作。我需要使queryOperation.desiredKeys = ["name", "address", "GpNumber"] 匹配showDetailVC 字符串就是这样，但图像无法显示在showDetailVC 我想需要更改代码detailpic.image = UIImage(named: "photoalbum") 但不知道该怎么做，你能修复代码？非常感谢您的帮助。

能不能再解释一下，queryOperation.desiredKeys = ["name", "address", "GpNumber"] 匹配showDetailVC是什么意思

是的！在我的项目中，我的showDetailVC'infoLabel.text = DisData?.object(forKey: "Gpaddress") as? String`nameLabel.text = DisData?.object(forKey: "GpName") as? StringmynumberLable.text = DisData?.object(forKey: "Gpnumber") as? StringforKeyes 和我之前发的不一样，因为我想让我的问题代码更容易被助手阅读。

所以您想将键 queryOperation.desireyKeys 传递给 showDetailVC？