不在iOS

Question

我使用MVC模式解析JSON中的UITableView值。为此，我创建了一个单独的UITableView swift类，Model类和UIViewController类as好。

我可以将JSON值解析为表视图。但问题是我无法使用委托方法将选定的tableView单元格值传递给控制器​​

我的代码是

UIVIewController：

class ViewController: UIViewController,contactSelectionDelegate {
var contactArray = [Address]()
@IBOutlet weak var userTable: UserTable!
let user = UserTable()


override func viewDidLoad() {
    super.viewDidLoad()

    user.userdelegate? = self
    if Connectivity.isConnectedToInternet() {
        print("Yes! Network connection is available")
        APIManager.sharedInstance.fetchUserDetails(urlString: FETCH_USER_DETAIL_URL, userCount: ["offset":1]) { connectionResult in

            switch connectionResult {
            case .success(let data):
                do {
                    self.contactArray = try JSONDecoder().decode([Address].self, from: data)

                    print(self.contactArray.count)
                    print(self.contactArray[0].Name)

                    DispatchQueue.main.async {
                        print(self.contactArray)
                        self.userTable.dataSourceArray=self.contactArray
                        self.userTable.reloadData()
                    }
                }
                catch let errorValue {
                    print(errorValue)
                }
            case .failure(let error):
                print(error)
            }
        }
    }
    else{
        print("No network connection")
    }
}

func selectedUserContact(name: String, email: String, phone: String) {
    print("Delegate Called")
    let userdetailVC = storyboard?.instantiateViewController(withIdentifier: "UserContactDetailPage") as! UserContactDetailPage
    userdetailVC.name = name
    userdetailVC.email = email
    userdetailVC.phone = phone
    self.navigationController?.pushViewController(userdetailVC, animated: true)
} }

UITableView：

protocol contactSelectionDelegate: class{
func selectedUserContact(name: String ,email: String ,phone: String)
}

class UserTable: UITableView ,UITableViewDelegate ,UITableViewDataSource  {


var dataSourceArray  =   [Address]()
weak var userdelegate: contactSelectionDelegate?

override init(frame: CGRect, style: UITableViewStyle) {
    super.init(frame: frame, style: style)
}

required init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)
}

override func awakeFromNib() {
    super.awakeFromNib()
    self.delegate=self
    self.dataSource=self
}

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

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

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

    let cell:UserCell   =   tableView.dequeueReusableCell(withIdentifier: "UserCell", for: indexPath) as! UserCell
    if self.dataSourceArray.count>0 {
        let myUser  =   self.dataSourceArray[indexPath.row]
        cell.nameLbl.text  =   myUser.Name
        cell.emailLbl.text  =   myUser.Email
        cell.phoneLbl.text =   myUser.Phone
    }
    return cell
}

func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    return 200
}

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    let myUser  =   self.dataSourceArray[indexPath.row]
    print(myUser.Name)
    print(myUser.Email)
    print(myUser.Phone)
     userdelegate?.selectedUserContact(name: myUser.Name, email: myUser.Email, phone: myUser.Phone)
}}

当我点击被调用的tableView单元格didSelectRowAtIndexPath方法上的表格时，selectedUserContact未被调用。

Answer 1

你误解了在这里委派的目的。这个想法是你的表视图只负责绘制一个表，它不应该负责维护它显示的任何数据。这允许您使用模型 - 视图 - 控制器（MVC）范例干净地设计代码。委派允许您的控制器在不破坏MVC的情况下将模型信息传递给视图。

在您的示例中：class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate { var contactArray = [Address]() @IBOutlet weak var userTable: UserTable! override func viewDidLoad() { super.viewDidLoad() if Connectivity.isConnectedToInternet() { print("Yes! Network connection is available") APIManager.sharedInstance.fetchUserDetails(urlString: FETCH_USER_DETAIL_URL, userCount: ["offset":1]) { connectionResult in switch connectionResult { case .success(let data): do { self.contactArray = try JSONDecoder().decode([Address].self, from: data) print(self.contactArray.count) print(self.contactArray[0].Name) DispatchQueue.main.async { print(self.contactArray) self.userTable.reloadData() } } catch let errorValue { print(errorValue) } case .failure(let error): print(error) } } } else{ print("No network connection") } } // MARK: - UITableViewDataSource func numberOfSections(in tableView: UITableView) -> Int { return 1; } func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int { return self.contactArray.count } func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell { let cell: UserCell = tableView.dequeueReusableCell(withIdentifier: "UserCell", for: indexPath) as! UserCell let myUser = self.contactArray[indexPath.row] cell.nameLbl.text = myUser.Name cell.emailLbl.text = myUser.Email cell.phoneLbl.text = myUser.Phone return cell } // MARK: - UITableViewDelegate func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat { return 200 } func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) { let myUser = self.contactArray[indexPath.row] print(myUser.Name) print(myUser.Email) print(myUser.Phone) selectedUserContact(name: myUser.Name, email: myUser.Email, phone: myUser.Phone) } // MARK: - func selectedUserContact(name: String, email: String, phone: String) { print("Delegate Called") let userdetailVC = storyboard?.instantiateViewController(withIdentifier: "UserContactDetailPage") as! UserContactDetailPage userdetailVC.name = name userdetailVC.email = email userdetailVC.phone = phone self.navigationController?.pushViewController(userdetailVC, animated: true) } } 是模型，表视图是视图，视图控制器是控制器。因此，您希望控制器符合表格视图的委托/数据源协议，以便它可以正确地将数据提供给它。

ViewController

编辑：我只想补充一点，您需要在故事板中确保将delegate设置为表格视图的dataSource和UserTable。然后，您可以删除您在UITableView课程中编写的所有代码。如果您根本不需要它，那么您的桌面视图可以很简单UITableViewCell。我几乎从不创建它的子类，因为你通常可以通过委托和DECLARE @Period INT = 7; WITH OrderedRankSets AS ( SELECT Quotes.StockID , Quotes.QuoteID , Quotes.QuoteDay , PriorQuotes.QuoteDay AS PriorQuoteDay , PriorQuotes.QuoteClose , ROW_NUMBER() OVER (PARTITION BY Quotes.StockID, Quotes.QuoteDay ORDER BY PriorQuotes.QuoteDay DESC) AS RowNumber , COUNT(*) OVER (PARTITION BY Quotes.StockID, Quotes.QuoteDay) AS [RowCount] FROM Quotes JOIN Quotes AS PriorQuotes ON (PriorQuotes.StockID = Quotes.StockID AND PriorQuotes.QuoteDay <= Quotes.QuoteDay) ) , RankedQuoteDays AS ( SELECT OrderedRankSets.* , CASE WHEN [RowCount] < @Period THEN NULL ELSE RANK() OVER (PARTITION BY StockID, QuoteDay ORDER BY QuoteClose DESC) END AS QuoteRank FROM OrderedRankSets WHERE RowNumber <= @Period ) SELECT RankedQuoteDays.StockID , RankedQuoteDays.QuoteID , RankedQuoteDays.QuoteDay , RankedQuoteDays.QuoteClose , RankedQuoteDays.QuoteRank FROM RankedQuoteDays WHERE QuoteDay = PriorQuoteDay ORDER BY StockID, QuoteDay 子类来完成所有事情。

Answer 2

根据这一行，您在故事板中有一个表格视图，并在viewcontroller中获取插座。

@IBOutlet weak var userTable: UserTable!

所以你不需要这样做：

let user = UserTable()

你必须给这样的代表：

userTable.userdelegate? = self

Answer 3

看起来您正在从故事板中实例化表视图，因此您不会在正确的UserTable实例上设置委托（并且因为委托是nil而永远不会调用委托方法）。

在视图控制器更改

中

user.userdelegate? = self

到

userTable.userdelegate? = self

Answer 4

对于我来说，它可以正常运行以下方案。请检查一下。

<强>用户表

@objc protocol contactSelectionDelegate: class {
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath)
}

weak var userdelegate: contactSelectionDelegate?
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        delegate?.tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath)
}

ViewController

class ViewController: UIViewController {

}

extension ViewController: contactSelectionDelegate {
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    // YOU CAN GET THE ALL THE STUFFS WHICH IS USER SELECTED IN THE TABLE VIEW
    }
}