//Swift 提醒框

   let alert = UIAlertController(title:"提示", message:"用户名或密码错误", preferredStyle: .alert)

   let cancel = UIAlertAction(title: "取消", style: .cancel, handler: { (action) in

                print("-------222222222222")

            })

   let ok = UIAlertAction(title: "确定", style: .default, handler: { (action) in

                print("-----------11111111")

            })

   alert.addAction(cancel)

   alert.addAction(ok)

   self.present(alert, animated: true, completion: nil)

//登录界面的View视图

import UIKit

class LoginView: UIView {

    var nameTextfiled :UITextField!

    var passworkTextfiled :UITextField!

    var loginButton:UIButton!

    var register : UIButton!

    override init(frame : CGRect)

    {

        super.init(frame: frame)

        self.backgroundColor = UIColor .red

        creatNameTextfiled()

        creatPassworkTextfiled()

        creatLoginBtn()

        creatRegisterBtn()

    }

    required init?(coder aDecoder: NSCoder) {

        fatalError("init(coder:) has not been implemented")

    }

    func creatNameTextfiled()  {

        nameTextfiled = UITextField()

        nameTextfiled.placeholder = "输入用户名"

        nameTextfiled.frame = CGRect(x: 20, y: 200, width: 335, height: 40)

        nameTextfiled.backgroundColor = UIColor.gray

        self.addSubview(nameTextfiled)

    }

    func creatPassworkTextfiled()  {

        passworkTextfiled = UITextField()

        passworkTextfiled.placeholder = "输入密码"

        passworkTextfiled.frame = CGRect(x: 20, y: 260, width: 335, height: 40)

        passworkTextfiled.backgroundColor = UIColor.gray

        self.addSubview(passworkTextfiled)

    }

    func creatLoginBtn() {

        loginButton = UIButton()

        loginButton.frame = CGRect(x: 20, y: 320, width: 100, height: 30)

        loginButton.setTitle("登录", for: .normal)

        loginButton.backgroundColor = UIColor.gray

        self.addSubview(loginButton)

    }

    func creatRegisterBtn() {

        register = UIButton()

        register.frame = CGRect(x: 255, y: 320, width: 100, height: 30)

        register.setTitle("注册", for: .normal)

        register.backgroundColor = UIColor.gray

        self.addSubview(register)

    }

}

//登录的Controller控制器

import UIKit

class LoginViewController: UIViewController ,UITextFieldDelegate {

    var codeV = LoginView()

    override func viewDidLoad() {

        super.viewDidLoad()

        self.view.backgroundColor = UIColor.white

        codeV = LoginView(frame: CGRect( x:0,y:0,width:375,height:667))

        codeV.nameTextfiled.delegate = self

        codeV.passworkTextfiled.delegate = self

        codeV.loginButton.addTarget(self, action: #selector(LoginViewController.loginEvent), for: .touchUpInside)

        codeV.register.addTarget(self, action: #selector(LoginViewController.registerEvent(textFd:)), for: .touchUpInside)

        self.view.addSubview(codeV)

    }

    func loginEvent () {

        print("==========")

    }

    func registerEvent(textFd :UITextField )   {

        print("------------")

        let reginserVc = RegisterViewController()

        self.navigationController?.pushViewController(reginserVc, animated:true)

    }

    //编辑结束时调用的方法

    func textFieldDidEndEditing(_ textField: UITextField) {

        if textField.placeholder == "输入用户名" {

            print("=========获得用户名")

        }else{

            print("=========获得密码")

        }

    }