Ios 如何创建代理以在另一个视图控制器的按钮单击时更改一个视图控制器中的标签名称_Ios_Swift

Ios 如何创建代理以在另一个视图控制器的按钮单击时更改一个视图控制器中的标签名称

ios swift

Ios 如何创建代理以在另一个视图控制器的按钮单击时更改一个视图控制器中的标签名称,ios,swift,Ios,Swift,这里我有两个视图控制器，在第二个视图控制器中单击按钮，我想更改第一个视图控制器中的标签名称，那么我如何才能做到这一点要更改用户名标签文本的第一个视图控制器 class MenuViewController1: UIViewController,UITableViewDataSource, UITableViewDelegate{ /** * Array to display menu options */ @IBOutlet var tblMenuOpt

这里我有两个视图控制器，在第二个视图控制器中单击按钮，我想更改第一个视图控制器中的标签名称，那么我如何才能做到这一点

要更改用户名标签文本的第一个视图控制器

class MenuViewController1: UIViewController,UITableViewDataSource, UITableViewDelegate{

    /**
     *  Array to display menu options
     */
    @IBOutlet var tblMenuOptions : UITableView!

    /**
     *  Transparent button to hide menu
     */
    @IBOutlet var btnCloseMenuOverlay : UIButton!

    /**
     *  Array containing menu options
     */
    var arrayMenuOptions = [Dictionary<String,String>]()

    /**
     *  Menu button which was tapped to display the menu
     */
    var btnMenu : UIButton!

    /**
     *  Delegate of the MenuVC
     */
    var delegate : SlideMenuDelegate?

  //  var delegateP: Profile?

    @IBOutlet weak var userProfilePhoto: UIImageView!

    @IBOutlet weak var userName: UILabel!

    override func viewDidLoad() {
        super.viewDidLoad()
        tblMenuOptions.tableFooterView = UIView()
        // Do any additional setup after loading the view.


        //let name = userName.text
        self.delegateP?.name_changed(name: userName.text!)

         }

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

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        updateArrayMenuOptions()
    }

    func updateArrayMenuOptions(){
        arrayMenuOptions.append(["title":"Home", "icon":"HomeIcon"])
        arrayMenuOptions.append(["title":"LogIn", "icon":"LogIn"])
        arrayMenuOptions.append(["title":"House Owner","icon":"House Owner"])
        arrayMenuOptions.append(["title":"ShortTerm", "icon":"ShortTerm"])
        arrayMenuOptions.append(["title":"LongTerm","icon":"LongTerm"])

        tblMenuOptions.reloadData()
    }

    @IBAction func onCloseMenuClick(_ button:UIButton!){
        btnMenu.tag = 0

        if (self.delegate != nil) {
            var index = Int32(button.tag)
            if(button == self.btnCloseMenuOverlay){
                index = -1
            }
            delegate?.slideMenuItemSelectedAtIndex(index)
        }

        UIView.animate(withDuration: 0.3, animations: { () -> Void in
            self.view.frame = CGRect(x: -UIScreen.main.bounds.size.width, y: 0, width: UIScreen.main.bounds.size.width,height: UIScreen.main.bounds.size.height)
            self.view.layoutIfNeeded()
            self.view.backgroundColor = UIColor.clear
        }, completion: { (finished) -> Void in
            self.view.removeFromSuperview()
            self.removeFromParentViewController()
        })
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell : UITableViewCell = tableView.dequeueReusableCell(withIdentifier: "cellMenu")!
        cell.selectionStyle = UITableViewCellSelectionStyle.none
        cell.layoutMargins = UIEdgeInsets.zero
        cell.preservesSuperviewLayoutMargins = false

        cell.backgroundColor = UIColor.clear


        let lblTitle : UILabel = cell.contentView.viewWithTag(101) as! UILabel
        let imgIcon : UIImageView = cell.contentView.viewWithTag(100) as! UIImageView

        imgIcon.image = UIImage(named: arrayMenuOptions[indexPath.row]["icon"]!)
        lblTitle.text = arrayMenuOptions[indexPath.row]["title"]!

        return cell
    }

    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        let btn = UIButton(type: UIButtonType.custom)
        btn.tag = indexPath.row
        self.onCloseMenuClick(btn)
    }

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

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

我们假设

MenuViewController

将被告知

LoginViewController

已完成登录。方法是：

首先，使用

LoginViewController

创建一个协议，并在

LoginViewController

中声明一个委托：

protocol LoginViewControllerDelegate:NSObjectProtocol {
    func LoginDidFinish()
}

class LoginViewController: UIViewController{

    weak var delegate:LoginViewControllerDelegate?
    //......
}

let loginViewController = LoginViewController()
loginViewController.delegate = self

第二步，登录完成后，调用委托方法：

Auth.auth().createUser(withEmail: email!, password: password!) { (user, error) in
    if (error == nil && (finalEmail != "") && self.isValidEmail(testStr: finalEmail!)) && (password != " " && self.isPasswordValid(password!)){
        self.displayMyAlertMessage(userMessage:"You are successfully registered ")
        self.delegate?.LoginDidFinish() //Key point
    }else{
        self.displayMyAlertMessage(userMessage:"Registration Failed.. Please Try Again !")
    }
};

第三个，在

菜单视图控制器

中，在创建

登录视图控制器

时，将

自身

指定为

登录视图控制器

的代理：

protocol LoginViewControllerDelegate:NSObjectProtocol {
    func LoginDidFinish()
}

class LoginViewController: UIViewController{

    weak var delegate:LoginViewControllerDelegate?
    //......
}

let loginViewController = LoginViewController()
loginViewController.delegate = self

最后，在

MenuViewController

中实现委托方法，登录完成后将调用该方法：

//MARK: - LoginViewControllerDelegate
func LoginDidFinish() {
    print("Login did finish")
    //And change your label's text here.
}