Question

我有一个带有单个textView的视图控制器，我从服务器获取一个字符串并在其上进行设置。

我在 viewDidAppear 中调用了http-get服务，我需要显示一个弹出警报，以等待用户获取字符串

我已尽一切努力，但无法在加载警报时关闭popalert和应用程序堆栈

    override func viewWillAppear(_ animated: Bool) {
        fetchAndPrintEachPerson()

        networkReachablity()

        popUpLoading() // start showing loading pop alert

        getPerson ()

    }

    override func viewDidLoad() {
        super.viewDidLoad()

        style()
        giftTextFiled.isEnabled = false



    }

    func popUpLoading(){

        popUpAlert = UIAlertController(title: nil, message: "wait ...", preferredStyle: .alert)

        let loadingIndicator = UIActivityIndicatorView(frame: CGRect(x: 10, y: 5, width: 50, height: 50))
        loadingIndicator.hidesWhenStopped = true
        loadingIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyle.gray
        loadingIndicator.startAnimating();

        popUpAlert.view.addSubview(loadingIndicator)
        present(popUpAlert, animated: true, completion: nil)


    }

    func getPerson(){

        guard let url=URL(string: "\(address)person/code") else {return}

        print(url)

        URLSession.shared.dataTask(with: url) { (data, response, error) in

            if let res=response {

                //print(res)
            }
            do {

                if let dataContent=data {

                    let con = try? JSONSerialization.jsonObject(with: dataContent, options: []) as? AnyObject
                    let data = con??["data"] as? AnyObject
                    let code = data?["code"] as? String
                    print(code)
                    // self.popUpAlert.dismiss(animated: true, completion: {
                     DispatchQueue.main.async(execute: {
                    //self.giftTextFiled.text=code!
                    self.giftTextFiled.isEnabled = true
                self.popUpAlert.dismiss(animated: true, completion: nil)

                     })
                    //})
                }else {
                    let snack=snackBarAlert()
                    snack.alert(title: "error", color: UIColor.red)
                    self.popUpAlert.dismiss(animated: true, completion: nil)
                }
            }catch let err{
                print(err)
DispatchQueue.main.async(execute: {
                self.popUpAlert.dismiss(animated: true, completion: nil)

})
            }
        }.resume()
    }

更新第一篇文章。

Answer 1

尝试将其放入DidLoad视图中，并检查是否从服务器获得了响应，否则它将通过else块掉落并继续显示弹出窗口

Answer 2

在非主线程上调用

URLSession.shared.dataTask完成关闭，这可能会为UI产生意外的结果。将您的UI代码分配到主线程。

URLSession.shared.dataTask(with: url) { (data, response, error) in
    DispatchQueue.main.async {
        // Your UI related code
    }
}.resume()

完成处理程序无法关闭popAlertController

2 个答案: