如何在加载了 JSON API 数据的 tableview 单元格中保存复选标记属性？

Question

我知道在手动将数据添加到数组时如何保存复选标记。我只是不知道当数据与 API 同步时如何保存单元格的复选标记属性。

这是我的代码：

class TableViewController: UITableViewController {

    let dataFilePath = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first?.appendingPathComponent("Items.plist")
    var fetchCoinInfo = [[String: AnyObject]]()
    let url = "https://api.coinmarketcap.com/v1/ticker/"

    override func viewDidLoad() {
        super.viewDidLoad()
        getCoinData(url: url)
        self.tableView.reloadData()
    }

    // MARK: - Table view data source

    override func numberOfSections(in tableView: UITableView) -> Int {
        // #warning Incomplete implementation, return the number of sections
        return 1
    }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        // #warning Incomplete implementation, return the number of rows
        return fetchCoinInfo.count
    }


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

        let cell = tableView.dequeueReusableCell(withIdentifier: "reuseIdentifier", for: indexPath)

        cell.textLabel?.text = fetchCoinInfo[indexPath.row]["name"] as? String
        cell.detailTextLabel?.text = fetchCoinInfo[indexPath.row]["symbol"] as? String

        return cell

    }

    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {

        tableView.deselectRow(at: indexPath, animated: true)
            let cell = tableView.cellForRow(at: indexPath)
        if cell?.accessoryType == .checkmark {
            cell?.accessoryType = .none
        }else {
            cell?.accessoryType = .checkmark
        }

    }

    func getCoinData(url: String) {

        // Alamofire parsing code:
        Alamofire.request(url, method: .get)
            .responseJSON { response in
                if response.result.isSuccess {

                    print("Sucess! Got the data")
                    let coinJSON : JSON = JSON(response.result.value!)
                    print(coinJSON)
                   self.updateCoinData(json: coinJSON)

                } else {
                    print("Error: \(String(describing: response.result.error))")
            }
        }
        self.tableView.reloadData()
    }

    // SwiftyJSON code:

    func updateCoinData(json : JSON) {

        if let coinSymbol = json[].arrayObject {
            print(coinSymbol)

            self.fetchCoinInfo = coinSymbol as! [[String: AnyObject]]
        }
        else {
            print("cannot connect to the server")
        }
        self.tableView.reloadData()
    }
}

Answer 1

请向您的本地 JSON 对象添加一个新键，其状态为复选标记，并在 didSelect 上更新它。您还需要在 cellForRowAtIndexPath 中设置附件视图

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

    let cell = tableView.dequeueReusableCell(withIdentifier: "reuseIdentifier", for: indexPath)

    var info = fetchCoinInfo[indexPath.row]
    cell.textLabel?.text = info["name"] as? String
    cell.detailTextLabel?.text = info["symbol"] as? String

    if let checked = info["checked"] as? Bool, checked == true {
        cell?.accessoryType = .checkmark
    }else {
        cell?.accessoryType = .none
        info["checked"] = false
    }

    return cell

}

override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {

    tableView.deselectRow(at: indexPath, animated: true)
    let cell = tableView.cellForRow(at: indexPath)
    var info = fetchCoinInfo[indexPath.row]
    if cell?.accessoryType == .checkmark {
        cell?.accessoryType = .none
        info["checked"] = false
    }else {
        cell?.accessoryType = .checkmark
        info["checked"] = true
    }

}