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////  CustomView.swift//  DemoApp////  Created by liuan on 2020/5/3.//  Copyright © 2020 anguo.com. All rights reserved.//import UIKit//自定义文本视图class CustomView: UIView,UITextFieldDelegate {    var textField:UITextField!    weak var controllor : ViewController?    override init(frame:CGRect){        super.init(frame: frame)        textField=UITextField(frame: CGRect(x: 0, y: 0, width: self.frame.size.width, height: self.frame.size.height))        textField.font=UIFont.boldSystemFont(ofSize: 14)        textField.textColor = .purple        textField.layer.shadowColor=UIColor.black.cgColor        textField.layer.shadowOffset = CGSize(width: 0.0, height: 3.0)        textField.layer.shadowOpacity=0.45        textField.layer.shadowRadius=3        textField.backgroundColor = .lightGray        textField.delegate=self        self.addSubview(textField)        }    func textFieldShouldReturn(_ textField: UITextField) -> Bool {        NotificationCenter.default.post(name: Notification.Name(rawValue: "checkFromNotification"),object: nil,userInfo: nil)        return true    }    required init?(coder: NSCoder) {        fatalError("init(coder:) has not been implemented")    }    }

////  ViewController.swift//  DemoApp////  Created by liuan on 2020/4/23.//  Copyright © 2020 anguo.com. All rights reserved.//import UIKitclass ViewController: UIViewController,UITextFieldDelegate {    var nameFiled:CustomView!    var passwordField:CustomView!    var submitButton:UIButton!            var animationView:UIView!    override func viewDidLoad(){        super.viewDidLoad()                let width=Int(self.view.frame.size.width)-40        let height=40        self.nameFiled = CustomView(frame: CGRect(x: 20, y: 60, width: width, height: height))        self.view.addSubview(self.nameFiled)                self.passwordField = CustomView(frame: CGRect(x: 20, y: 140, width: width, height: height))        self.view.addSubview(self.passwordField)                self.submitButton = UIButton(frame: CGRect(x: 20, y: 240, width: width, height: height))        self.submitButton.setTitle("提交", for: .normal)        self.submitButton.backgroundColor = .gray        self.submitButton.isEnabled=false        self.submitButton.addTarget(self, action: #selector(ViewController.submitForm(_:)), for: .touchUpInside)        self.view.addSubview(self.submitButton)        NotificationCenter.default.addObserver(self, selector: #selector(checkForm(_:)), name: NSNotification.Name(rawValue: "checkFromNotification"), object: nil)    }        @objc func submitForm(_ sender:UIButton){        print("submitForm(_:)")    }    @objc func checkForm(_ notifiy:Notification?){        if self.nameFiled.textField.text != "" && passwordField.textField.text != ""{            self.submitButton.isEnabled = true            self.submitButton.backgroundColor = .orange        }else{            self.submitButton.isEnabled = false                self.submitButton.backgroundColor = .gray        }    }    func textFieldShouldReturn(_ textField: UITextField) -> Bool {        checkForm()        return true    }    func checkForm() {        if self.nameFiled.textField.text != "" && self.passwordField.textField.text != ""        {            self.submitButton.isEnabled=true            self.submitButton.backgroundColor = .orange        }else{            self.submitButton.isEnabled=false            self.submitButton.backgroundColor = .gray        }    }    deinit {        NotificationCenter.default.removeObserver(self)    }        }

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