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在tableview单元格中显示列数据-为什么不创建和填充我的表单元格?

[英]Display column data in tableview cell - Why aren't my table cells being created and populated?

When I build and run, my table is empty. 当我生成并运行时,我的表是空的。 I have verified my connection with the database. 我已经验证了与数据库的连接。 When I hard code the data, it works just fine. 当我对数据进行硬编码时,它就可以正常工作。 I assume my code implementation is incorrect as this is the first time I've used Parse. 我认为我的代码实现不正确,因为这是我第一次使用Parse。

import UIKit

class ListSubViewController: UITableViewController {
    var vendorArray : NSMutableArray = []

    override func viewDidLoad() {
        super.viewDidLoad()

        let query = PFQuery (className: "Vendor")
        query.order(byAscending: "ID")
        query.findObjectsInBackground {
            (objects:[PFObject]?, error:Error?) -> Void in

            if error == nil {
                if let objects = objects {

                    print("\(objects.count) vendors are listed")
                    for object in objects {
                        self.vendorArray.add(object)
                    }
                    self.tableView.reloadData()
                }
            } else {
                print("There is an error")
            }
        }
    }

    override func numberOfSections(in tableView: UITableView) -> Int {
        return 1
    }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return self.vendorArray.count
    }

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {

        let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! TableViewCell

        let vendorObjects = vendorArray[indexPath.row] as! PFObject
        let vendorName = vendorObjects["vendorName"] as! String
        let image = vendorObjects["Image"] as! PFFile

        cell.vendorLabel.text = vendorName
        image.getDataInBackground(block: {
            (result, error) in
            cell.vendorImage.image = UIImage(data: result!)
        })

        self.tableView.reloadData()
        return cell
    }

Putting this line 把这条线

self.tableView.reloadData()

inside cellForRowAt causes a recursive - endless process as the table is reloaded for every cell creation cellForRowAt内部会导致递归-无休止的过程,因为每次创建单元时都会重新加载表

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