如何在某些数据更改后刷新TableView？

Question

我想只改变一个类的用户列表，称为网络。我不明白如何在userList更改后进行TableView更新。我将在下面的代码中向您展示一个示例和详细问题。

// Network.swift 
class Network { 
    var userList: [User] = [] 

    // Next functions may change userList array 
    // For example, the data came from the server, and update the userList with new data 
} 

// App delegate 
class AppDelegate: UIResponder, UIApplicationDelegate { 
    var network: Network = Network() 

    .. 
} 

// File TableViewController.swift 
class TableViewController: UITableViewController { 
    … 
    var userList: [User] = [] // Here I want to have a full copy of the array from Network class 

    override func viewDidLoad() { 
     super.viewDidLoad() 

     let appDelegate = UIApplication.shared.delegate as! AppDelegate 
     self.userList = appDelegate.network.userList // Just copy an array 
     // And I want that after each update appDelegate.network.userList I updated the table, how to do it better? 

     self.tableView.reloadData() 
    } 
} 

Answer 1

您可以使用通知。每当用户列表被更新，发布这样的通知：

NotificationCenter.default.post(name: NSNotification.Name(rawValue: "UserlistUpdate"), object: nil) 

然后，在viewDidLoad中添加：

NotificationCenter.default.addObserver(self, selector: #selector(TableViewController.reloadData), name: NSNotification.Name(rawValue: "UserlistUpdate"), object: nil) 

附：关于你的架构到目前为止，我会让TableViewController为Network保留一个变量，而不是保存自己的用户数组。然后，在AppDelegate中：

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool { 
    // Override point for customization after application launch. 
    let network = Network() 

    // Access the TableViewController and set its network variable 
    let tableViewController = window!.rootViewController as! TableViewController 
    tableViewController.network = network 

Answer 2

由于@JDM在评论中提到您的架构是混乱的。
尝试使用协议来做到这一点代表团：

// Network.swift 
protocol UsersUpdatedProtocol { 
    func usersListUpdated(list: [User]) 
} 
class Network { 
    var userList: [User] = [] { 
    didSet { 
     delegate?.usersListUpdated(list: userList) 
    } 
    } 
    var delegate: UsersUpdatedProtocol? 
    init(delegate d: UsersUpdatedProtocol) { 
    super.init() 
    delegate = d 
    } 
} 

// File TableViewController.swift 
class TableViewController: UITableViewController, UsersUpdatedProtocol { 
    var userList: [User] = [] 

    override func viewDidLoad() { 
    super.viewDidLoad() 
    let _ = Network(delegate: self) 
    } 
    func usersListUpdated(list: [User]) { 
    self.userList = list 
    self.tableView.reloadData() 
    } 
}