swift - 快速访问协议(protocol)方法中的变量

Question

任何人都可以帮助我使用这个快速代码，我是一个快速初学者。我正在尝试使用 MVC 创建一个登录页面，它看起来像这样 enter image description here

因此，当用户输入登录信息并且 JSON 数据的状态为“s”(表示成功登录)时，它应该显示一些测试信息，而当登录状态为“f”(表示登录失败)时，它应该保留在同一个登录页面，我尝试访问以下代码中协议(protocol)方法中的状态:

因此，每当用户按下按钮时，它都应该采取所需的操作，但下面代码中的状态为零，因此每当我运行应用程序时，无论登录是否成功，都会显示信息

//this piece of code is in the LoginViewController
        func didReceivedLoginInfo(info : [LoginModel]) -> String
            {
                self.loginData = info
                print("didReceivedLOOGIN count is \(loginData!.count)")//the print is successful here
                for i in 0..<loginData!.count
                {
                    print("LoginData Info : \(loginData![i])")//the print is successful here
                }
                statuss = loginData![0].status
                print("HERE YOU GO, THIS IS WHAT I FOUND: \(statuss!)")//the print is successful here
               return statuss! 
            }

//this piece of code is in the LoginViewController
    func buttonAction(sender:UIButton!)
        {
            var btnsendtag: UIButton = sender
                var uName  = username!.text as? String!
                var uPass  = password!.text as? String!
                parser = LoginParser()
                parser!.getLoginInfo(uName!, pass: uPass!)
                var status = loginData?[0].status
                print("from View Controller this is the msg: \(status)")
                parser!.delegate = self
                if status == "s"            {
                    print("from View Controller this is the status: \(status)")
                    let vc = ViewController()
                    let navigationController = UINavigationController(rootViewController: vc)
                    self.presentViewController(navigationController, animated: true, completion: nil)
                }

                else {
                    let vc = LoginViewController()
                    let navigationController = UINavigationController(rootViewController: vc)
                    self.presentViewController(navigationController, animated: true, completion: nil)
                           }
        }



     ////this piece of code is in the LoginParser
        import UIKit

        @objc protocol LoginParserDelegate : NSObjectProtocol

        {

            func didReceivedLoginInfo (info : [LoginModel]) -> String

            optional func didRecivedError()

        }



        class LoginParser: NSObject {

            // var  webData: NSMutableData?

            var webData: NSData?
            weak var delegate : LoginParserDelegate?
            var name = String ()
            var model : LoginModel?
            var alertView:UIAlertView?
            var MainLogin : [LoginModel] = []

            func getLoginInfo (usern : String, pass : String){

                var post:NSString = "LID=\(usern)&PWD=\(pass)&Passcode=s@v#"
                var url:NSURL = NSURL(string: "some link")!
                var postData:NSData = post.dataUsingEncoding(NSUTF8StringEncoding)!
                var postLength:NSString = String( postData.length )

                var request:NSMutableURLRequest = NSMutableURLRequest(URL: url)

                request.HTTPMethod = "POST"

                request.HTTPBody = postData

                request.setValue(postLength as String, forHTTPHeaderField: "Content-Length")

                request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")

                request.setValue("application/json", forHTTPHeaderField: "Accept")

                var response: NSURLResponse?

                let connection = NSURLConnection(request: request, delegate: self)
            }


            func connection(connection: NSURLConnection, didFailWithError error: NSError){

                if delegate != nil {
                    if delegate!.respondsToSelector(Selector("didRecivedLoginInfo")){
                        delegate!.didRecivedError!()
                    }

                }
            }

            func connection(connection: NSURLConnection, didReceiveResponse response: NSURLResponse){

                webData = NSData()


            }

            func connection(connection: NSURLConnection, didReceiveData data: NSData){

                webData! = data
            }

            func connectionDidFinishLoading(connection: NSURLConnection){
                let responseString = NSString(data: webData!, encoding: NSUTF8StringEncoding)
                print("responseString \(responseString!)")

                processUserTypes ()

            }

            func processUserTypes ()->[LoginModel]
            {
                model = LoginModel()

                // Process JSON

                do {
                    let result = try NSJSONSerialization.JSONObjectWithData(webData!, options: NSJSONReadingOptions.MutableContainers)as? NSDictionary


                    var Login = LoginModel()


                    let status = result?.objectForKey("Status") as? String
                    let msg = result?.objectForKey("En") as? String
                    let employeename=result?.objectForKey("DisplayName")as? String
                    print("STATUS IN PARSER IS \(status!)")

                    if status == "s"

                    {

                        print(status!)
                        Login.name = employeename
                        Login.status = status
                        Login.message = msg
                        alertView = UIAlertView()
                        alertView!.title = "Login successful"
                        alertView!.message = "Welcome \(employeename!)"
                        alertView!.delegate = self
                        alertView!.addButtonWithTitle("OK")
                        alertView!.show()
                        MainLogin.append(Login)
                        print("count in login is  \(MainLogin.count)")
                        if delegate != nil
                        {
                            delegate!.didReceivedLoginInfo(MainLogin)
                        }

                    }

                    else

                    {
                        Login.message = msg
                        alertView = UIAlertView()
                        alertView!.title = "Login failed"
                        alertView!.message = msg!
                        alertView!.delegate = self
                        alertView!.addButtonWithTitle("OK")
                        alertView!.show()

                        MainLogin.append(Login)
                        print("this is the main login\(MainLogin)")


                    }

                           }
                catch {

                    if delegate != nil {
                        if delegate!.respondsToSelector(Selector("didRecivedLoginInfo")){
                            delegate!.didRecivedError!()
                        }


                    }



                }
                return MainLogin
            }
        }

有人可以帮我解决这个问题吗？谢谢

Answer 1

您在processUserTypes内调用didReceivedLoginInfo，该过程在connectionDidFinishLoading内调用。 buttonAction 调用 getLoginInfo，后者执行异步请求，完成后将回调 connectionDidFinishLoading。

此 getLoginInfo 将在发送请求、接收响应并调用 connectionDidFinishLoading 之前返回很长时间。

=> 调用 getLogininfo 后您将无法执行任何操作

=>

给你按钮方法

1. 创建解析器
2. 设置委托(delegate)
3. 调用 getLoginInfo
4. 不要在这里做任何有潜在结果的事情

用于 didReceiveLoginInfo。

你可以在那里做进一步的逻辑，甚至可能是用户界面的东西(你必须将影响用户界面的逻辑包装在

dispatch_async(dispatch_get_main_queue()){
     //here
}

通话