ios - 在 Swift 2 中使用 Parse 检索数据

Question

我这样做是为了获取数据并将其显示在表格 View 中但它没有显示任何内容。

我使用了这段代码:

import UIKit
import Parse
import Bolts

class Parsedata: UIViewController, UITableViewDelegate, UITableViewDataSource {
    //@IBOutlet var NTableView: UITableView!

    @IBOutlet var NTableView: UITableView!
    var NArray:[String] = [String]()




    override func viewDidLoad() {
        super.viewDidLoad()



        // Do any additional setup after loading the view, typically from a nib.

        self.NTableView.delegate = self
        self.NTableView.dataSource = self


        // retrieve notification from parse
        self.RetrieveN()
        NSLog("Done with it")

    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    func RetrieveN () {

        //create a pfquery
        var query:PFQuery = PFQuery(className: "Notification")

        //call findobject in background
        query.findObjectsInBackgroundWithBlock { (objects, error) -> Void in

            //clear the Narray

            self.NArray = [String]()

            //loop through the objects array
            for Nobject in objects!{

                //retrieve the text column value of each PFobject
                let Ntext:String? = (Nobject as! PFObject) ["Text"] as? String


                // assign it into your Narray

                if Ntext != nil {
                self.NArray.append(Ntext!)

                }

            }

            if error == nil {
                // The find succeeded.
                print("Successfully retrieved \(objects!.count) Notifications.")}
           //reload the table view
            self.NTableView.reloadData()
            }
    }

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

        let cell = self.NTableView.dequeueReusableCellWithIdentifier("NCell") as UITableViewCell?

        cell?.textLabel?.text = self.NArray[indexPath.row]

        return cell!

    }


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

        return NArray.count
    }
}

它工作正常，因为它显示在 LOG 容器中检索到 3 个对象。

Answer 1

除非您的代码比此处发布的代码多，否则您还需要实现 numberOfSectionsInTableView 并返回 1