Question

尝试使用Swift 3在Xcode中显示jSON数据时出现构建错误。我将把我的部分代码复制到此页面，希望你们能帮助我。

我在本网站上发现了类似的问题，但答案似乎没有帮助。

 class FilmsViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
    weak var tableView : UITableView!
    var FilmArray = [String]()

    let film_url = "https://www.testing.com/api/resources/films/1"
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return 1
    }
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {


        let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for:indexPath) as! FilmsAPITableViewCell        
        // Adding the right informations
        cell.movieTitle.text = FilmArray[indexPath.row]
        // Returning the cell
        return cell
    }
    // @IBOutlet weak var FilmsView: UITableView!
    //    weak var tableView : UITableView!
    //    var FilmArray = [String]()
    //
    //    let film_url = "https://www.distribber.com/api/resources/films/1"
    //
    override func viewDidLoad() {
        super.viewDidLoad()

        let tableView = UITableView (frame:view.bounds)
        view.addSubview(tableView)
        self.tableView = tableView

        tableView.dataSource = self
        tableView.delegate = self


        //        func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        //            return 1
        //        }
        //            func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        //                // Getting the right element
        //               //let films = FilmArray[indexPath.row]
        //
        //
        //                // Instantiate a cell
        //                //let cell = UITableViewCell(style: .subtitle, reuseIdentifier: "moviecell")
        //                let cell = tableView.dequeueReusableCell(withIdentifier: "cell") as! FilmsAPITableViewCell
        //                //        cell.movieTitle.text = FilmArray[indexPath.row]
        //                // Adding the right informations
        //                cell.movieTitle.text = FilmArray[indexPath.row]
        //                // Returning the cell
        //                return cell
        //        }
        // }

        //}



        let url:URL = URL(string: film_url)!
        let session = URLSession.shared

        let request = NSMutableURLRequest(url: url)
        request.httpMethod = "GET"
        request.setValue("740c94c51891c02b64d6c78840b478fe0b02fe2c", forHTTPHeaderField: "X-API-KEY")
        request.setValue("Basic YmhlZW0uZW5nckBnbWFpbC5jb206YmgzM20=", forHTTPHeaderField: "Authorization")
        request.cachePolicy = NSURLRequest.CachePolicy.reloadIgnoringCacheData
        let paramString = ""


        //        for (key, value) in post_data
        //        {
        //            paramString = paramString + (key as! String) + "=" + (value as! String) + "&"
        //        }
        //
        request.httpBody = paramString.data(using: String.Encoding.utf8)

        let task = session.dataTask(with: request as URLRequest, completionHandler: {
            (
            data, response, error) in

            guard let _:Data = data, let _:URLResponse = response  , error == nil else {

                return
            }



            let json: Any?

            do
            {
                json = try JSONSerialization.jsonObject(with: data!, options: [])

                //  Prasing JSON
                var parsedData = try JSONSerialization.jsonObject(with: data!, options: []) as! [String:Any]
                print(parsedData)
                if let FilmArray = parsedData["films"] as? NSArray {
                    for movieTitle in FilmArray{
                        if let filmDict = movieTitle as? NSDictionary{
                            if let film = filmDict.value(forKey: "title") {
                                self.FilmArray.append(film as! String)
                            }

                            OperationQueue.main.addOperation({
                            self.tableView.reloadData()
                             })

                        }
                    }

                }
                print("Hello")
                self.tableView.reloadData()
                print(self.FilmArray)
            }
            catch
            {
                return
            }

            guard let server_response = json as? NSDictionary else
            {
                return
            }


            if let data_block = server_response["data"] as? NSDictionary
            {
                if let session_data = data_block["session"] as? String
                {
                    //  self.login_session = session_data

                    let preferences = UserDefaults.standard
                    preferences.set(session_data, forKey: "session")

                    //  DispatchQueue.main.async(execute: self.LoginDone)
                }
            }



        })

        task.resume()

        // Do any additional setup after loading the view.
    }

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



}

这里也是FilmsAPITableViewCell.swift

的输出

import UIKit

导入UIKit

class FilmsAPITableViewCell: UITableViewCell {
    @IBOutlet weak var movieTitle: UILabel!

    override func awakeFromNib() {
        super.awakeFromNib()
        // Initialization code
    }

    override func setSelected(_ selected: Bool, animated: Bool) {
        super.setSelected(selected, animated: animated)

        // Configure the view for the selected state
    }

}

Answer 1

movieTitle为零的原因是因为您的自定义单元格类没有该标签插座。您需要在.xib（或故事板）中创建UILabel，并在自定义单元类中创建插座连接。

您的完成块中似乎没有self.tableView.reloadData()。尝试在print("Hello")行之后添加。

P.S。不要忘记将重新加载到主队列。

以下是我编辑的代码，以使其正常工作：

override func viewDidLoad() {
    super.viewDidLoad()

    tableView.dataSource = self
    tableView.delegate = self

    let url:URL = URL(string: film_url)!
    let session = URLSession.shared

    let request = NSMutableURLRequest(url: url)
    request.httpMethod = "GET"
    request.setValue("740c94c51891c02b64d6c78840b478fe0b02fe2c", forHTTPHeaderField: "X-API-KEY")
    request.setValue("Basic YmhlZW0uZW5nckBnbWFpbC5jb206YmgzM20=", forHTTPHeaderField: "Authorization")
    request.cachePolicy = NSURLRequest.CachePolicy.reloadIgnoringCacheData
    let paramString = ""

    request.httpBody = paramString.data(using: String.Encoding.utf8)

    let task = session.dataTask(with: request as URLRequest, completionHandler: {
        (
        data, response, error) in

        guard let _:Data = data, let _:URLResponse = response  , error == nil else {

            return
        }



        var json:Any?

        do
        {
            if let existingData = data {
                json = try JSONSerialization.jsonObject(with: existingData, options: [])
            }

            //  Prasing JSON
            if let parsedData = json as? [[String:Any]] {
                for dict in parsedData {
                    if let title = dict["title"] as? String {
                        self.FilmArray.append(title)
                    }
                }

                OperationQueue.main.addOperation({
                    self.tableView.reloadData()
                })
            }
        }
        catch
        {
            return
        }

        guard let server_response = json as? NSDictionary else
        {
            return
        }

        if let data_block = server_response["data"] as? NSDictionary
        {
            if let session_data = data_block["session"] as? String
            {
                //  self.login_session = session_data

                let preferences = UserDefaults.standard
                preferences.set(session_data, forKey: "session")

                //  DispatchQueue.main.async(execute: self.LoginDone)
            }
        }
    })

    task.resume()
}

UITable不会显示。价值类型＆＃39; FilmsAPITableViewCell＆＃39;没有会员＆＃39; movieTitle＆＃39;

1 个答案: