json - UITableView 不使用 SwiftyJSON 和 Alamofire 加载数据

Question

我正在尝试解析 json 并将其加载到 CustomTable 中，我的 json 解析成功，但无法在 UI 中加载数据，我尝试添加测试数据，然后显示出来。所以我想这与范围界定有关。我尝试过在同一问题上使用其他答案，但仍然不起作用

import UIKit
import Alamofire
import SwiftyJSON

class NewsViewController: UIViewController, 
   UITableViewDelegate, UITableViewDataSource {

     @IBOutlet weak var tableView: UITableView!



    var newsPosts = [NewsPost]()

    override func viewDidLoad() {
        super.viewDidLoad()

        tableView.delegate = self
        tableView.dataSource = self

        getNewsPost()


    }

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

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

        let post = newsPosts[indexPath.row]

        if let cell = tableView.dequeueReusableCell(withIdentifier: "NewsCell") as? NewsPostCell{
        cell.configureCell(post: post)
        return cell
    }else{
        let cell = NewsPostCell()
        cell.configureCell(post: post)
        return cell
    }
}


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


func getNewsPost(){
    Alamofire.request(URL_BASE + NEWS_URL).responseJSON { response in


        let json = JSON(data: response.data!)

        if let dict = json.dictionaryObject{
            if let result = dict["data"] as? [NSDictionary]{
                for data in result{
                    guard let title = data["title"] as? String else{
                        return print("title is nil")
                    }
                    guard let href = data["href"] as? String else{
                        return print("href is nil")
                    }
                        guard let image = data["image"] as? String else{
                            return print("image is nil")
                        }
                        guard let content = data["content"] as? String else{
                            return print("content is nil")
                        }
                        guard let _ = data["timestamp"] as? String else{
                            return print("timestamp is nil")
                        }
                        guard let type = data["type"] as? String else{
                            return print("type is nil")
                        }

                        print(type)

                        let post = NewsPost(title: title, href: href, 
                        image: image, timestamp: 
                        "1 day ago", content: content, type: type)

                        self.newsPosts.append(post)
                    }
                    self.tableView.reloadData()
                }
            }
        }
    }


}

Answer 1

您应该在重新加载数据之前测试您的表格 View 是否已初始化:

import UIKit
import Alamofire
import SwiftyJSON

class NewsViewController: UIViewController, 
   UITableViewDelegate, UITableViewDataSource {

     @IBOutlet weak var tableView: UITableView!



    var newsPosts = [NewsPost]()

    override func viewDidLoad() {
        super.viewDidLoad()

        tableView.delegate = self
        tableView.dataSource = self

        getNewsPost()


    }

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

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

        let post = newsPosts[indexPath.row]

        if let cell = tableView.dequeueReusableCell(withIdentifier: "NewsCell") as? NewsPostCell{
        cell.configureCell(post: post)
        return cell
    }else{
        let cell = NewsPostCell()
        cell.configureCell(post: post)
        return cell
    }
}


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


func getNewsPost(){
    Alamofire.request(URL_BASE + NEWS_URL).responseJSON { response in


        let json = JSON(data: response.data!)

        if let dict = json.dictionaryObject{
            if let result = dict["data"] as? [NSDictionary]{
                for data in result{
                    guard let title = data["title"] as? String else{
                        return print("title is nil")
                    }
                    guard let href = data["href"] as? String else{
                        return print("href is nil")
                    }
                        guard let image = data["image"] as? String else{
                            return print("image is nil")
                        }
                        guard let content = data["content"] as? String else{
                            return print("content is nil")
                        }
                        guard let _ = data["timestamp"] as? String else{
                            return print("timestamp is nil")
                        }
                        guard let type = data["type"] as? String else{
                            return print("type is nil")
                        }

                        print(type)

                        let post = NewsPost(title: title, href: href, 
                        image: image, timestamp: 
                        "1 day ago", content: content, type: type)

                        self.newsPosts.append(post)
                    }
                    if self.tableView != nil {
                        self.tableView.reloadData()
                    }
                }
            }
        }
    }


}