1.什么是MVP?
MVP是模型(Model)、视图(View)、主持人(Presenter)的缩写,分别代表项目中3个不同的模块。
1.1 模型 (Model):负责处理数据的加载或存储
1.2 视图 (View):负责界面数据的展示与用户交互
1.3 主持人(Presenter):是Model和View之间的桥梁,将两者进行链接。
整个交互流程看起来大致是这样的:
用户交互->View获得交互事件->View将事件转发给Presenter->Presenter调用Model获取新数据->Presenter将数据推送给View进行展示
案例1:
这里我们用app开发中常用的登录功能为例,用mvp来实现一个登录逻辑(功能)。既然用MVP 那么我们得新建三个类即:LoginModel,LoginPresenter,LoginView
class loginPresenter: NSObject { //声明V和M2个属性,其中的V中写了代理,待优化 private var loginViewDelegate:LoginViewDelegate? private var loginModel:LoginModel? //实例化 override init() { //model实例化 self.loginModel = LoginModel() } //V层调用这个login方法,这个方法再调用M层的login方法 func login(usrName: String, pwd: String) { self.loginModel?.login(usrName: usrName, pwd: pwd, callback: { (result) in //从m层的的回调,回调到v层去,同样还是通过一个代理实现 self.loginViewDelegate?.onLoginResult(result: result) }) } //绑定V和P func attachView(viewDelegate:LoginViewDelegate) { self.loginViewDelegate = viewDelegate } //解除绑定,假如网络请求是,viewController已经释放,则无需再回调更新UI func detachView() { self.loginViewDelegate = nil } }
import Foundation //M层 class LoginModel: NSObject { //登陆的方法,P层调用这个方法来发起登陆请求 func login(usrName:String,pwd:String,callback:((String)->Void)) { //发起网络请求 处理方法要封装,不能耦合 print("进入model") //调用网络模块方法 HttpUtils.post(usrName: usrName, pwd: pwd) { (result) in //1,处理网络返回的情况,如:登录成功要缓存个人信息 //...... //2,完成登录数据处理,回调给P层,这里不与UI部分耦合 callback(result) } } }
import UIKit //遵循LoginViewDelegate协议 class ViewController: UIViewController,LoginViewDelegate { //定义一个presenter,实例化 private let presenter = loginPresenter() override func viewDidLoad() { super.viewDidLoad() //添加v和p2层的绑定 self.presenter.attachView(viewDelegate: self) //UI层交互操作,发起登录请求 self.presenter.login(usrName: "ZZB", pwd: "123456") } //依据P层的回调数据进行V层UI更新 func onLoginResult(result: String) { print("处理P层返回的数据: \(result),更新UI") } override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() //页面注销的时候解除绑定 self.presenter.detachView() } }
案例2:
class ViewController: UIViewController { fileprivate lazy var presenter : ViewPresenster = { return ViewPresenster(presenter: self) }() override func viewDidLoad() { super.viewDidLoad() } override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) { presenter.getData() } } // MARK:- 获取数据// extension ViewController:ViewPresensterProtocol{ func showPost(_ resulet: [DCModel]) { print(resulet) } }
import UIKit protocol ViewPresensterProtocol { func showPost(_ resulet: [DCModel]) } class ViewPresenster: NSObject { var presenter: ViewPresensterProtocol! lazy var model:[DCModel] = [DCModel]() init(presenter:ViewPresensterProtocol) { self.presenter = presenter; } func getData(){ let dict = [ ["user_id":"1","user_name":"zhaodacai1"], ["user_id":"2","user_name":"zhaodacai2"], ["user_id":"3","user_name":"zhaodacai3"], ["user_id":"4","user_name":"zhaodacai4"], ["user_id":"5","user_name":"zhaodacai5"], ["user_id":"6","user_name":"zhaodacai6"], ["user_id":"7","user_name":"zhaodacai7"] ] for item in dict { model.append(DCModel(dict: item)) } self.presenter.showPost(model) } }
import UIKit class DCModel: NSObject { // 用户ID var user_id : String = "" // 用户名字 var user_name : String = "" init(dict : [String : Any]) { super.init() setValuesForKeys(dict) } override func setValue(_ value: Any?, forUndefinedKey key: String) {} }
参考链接: