ios - 在 HTTP 方法中使用 POST 请求保存 UI？

Question

当我点击按钮时，它将执行服务请求操作。根据结果，它将重定向到下一个 View Controller 。加载 Next View Controller 后，会保留或阻止 UI。如何解决这个问题？我是第一次快速使用 RestAPI 和 GCD，所以不知道如何解决这个问题......

这是登录按钮

@IBAction func btnLogin(_ sender: Any)
    {
        self.api()
    }

这就是我们所说的函数。

func api()
    {
        let myURL = URL(string: "http://www.digi.com/laravel_api_demo/api/demoapipost")

        let request = NSMutableURLRequest(url: myURL!)
        request.httpMethod = "POST"



        let strEmail = tfLgnID.text
        let strPwd = tfPwd.text


        let postString = ["username":strEmail, "password":strPwd]
        //let postString = ["username":"ayush", "password":"abc"]


        request.addValue("application/json", forHTTPHeaderField: "Content-Type")
        request.addValue("application/json", forHTTPHeaderField: "Accept")

        //create the session object
        //let session = URLSession.shared

        do {
            request.httpBody = try JSONSerialization.data(withJSONObject: postString, options: .prettyPrinted) // pass dictionary to nsdata object and set it as request body
            print("Successfully passed data to server")
        } catch let error {
            print(error.localizedDescription)
        }

        let postTask = URLSession.shared.dataTask(with: request as URLRequest) { (data, response, error) in

            guard error == nil else {
                return
            }

            guard let data = data else {
                return
            }

            do {
                //create json object from data
                if let json = try JSONSerialization.jsonObject(with: data, options: .mutableContainers) as? [String: Any] {
                    print("POST Method :\(json)")

                    let dict = json as? [String: Any]
                    let num = dict!["status"]
                    print("Status : \(num)")
                    print("Dict : \(dict)")
                    print("username : \(dict!["username"])")
                    print("password : \(dict!["password"])")

                    if dict!["status"] as! Int == 1
                    {
                        print("Successfully Logged In")


                        DispatchQueue.main.async {
                            let visitorVC = self.storyboard?.instantiateViewController(withIdentifier: "VisitorVC") as! VisitorVC
                            self.present(visitorVC, animated: true, completion: nil)

                        }

                        print("OK")
                    }
                    else
                    {
                        print("Not OK")
                    }



                    // handle json...
                }
            } catch let error {
                print(error.localizedDescription)
            }
        }
        postTask.resume()


        }

Answer 1

试试这个方法

  func api() {
    var request = URLRequest(url: URL(string: "")!) // put your url
    request.httpMethod = "POST"
      let strEmail = tfLgnID.text
    let strPwd = tfPwd.text
     let postString:String = "user_id=\(strEmail)&user_id=\(strPwd)"
    request.httpBody = postString.data(using: .utf8)
    let task = URLSession.shared.dataTask(with: request) { data, response, error in
        guard let data = data, error == nil else {                                                 // check for fundamental networking error
            print("error=\(String(describing: error))")
            return
        }
        do {
            if let jsonResult = try JSONSerialization.jsonObject(with: data, options: JSONSerialization.ReadingOptions.mutableContainers) as? NSDictionary {
                print(jsonResult)
                let status = jsonResult["status"]! as! NSString
                print("status\(status)")

                    DispatchQueue.main.async(execute: {
                       // your error Alert

                    })

                }
                else {
                            DispatchQueue.main.async(execute: {
                                    let visitorVC = self.storyboard?.instantiateViewController(withIdentifier: "VisitorVC") as! VisitorVC
                                    self.present(visitorVC, animated: true, completion: nil)


                        })
                    }
                }
            } catch let error as NSError {
                print(error.localizedDescription)
        }

        if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 {           // check for http errors
            print("statusCode should be 200, but is \(httpStatus.statusCode)")
            print("response = \(String(describing: response))")

        }

        let responseString = String(data: data, encoding: .utf8)
        print("responseString = \(String(describing: responseString))")
    }
    task.resume()

}