ios – 在Swift 3中不会忽视进度警报

我正在尝试创建一个函数来显示和解除 Swift 3中的ProgressDialog.但在此代码中,对话框不会从视图控制器中消失.

func showLoadingDialog(show : Bool)  {
    if show {
        self.alert = UIAlertController(title: nil,message: "Please 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()
        self.alert.view.addSubview(loadingInDicator)
        self.present(self.alert,animated: true,completion: nil)
    }else{
        self.dismiss(animated: false,completion: nil)
    }
}

我也尝试了以下方法来关闭此对话框,但它们都没有工作：

self.alert.view.removeFromSuperview()

self.alert.view.alpha = 0
self.presenTingViewController?.dismiss(animated: true,completion: nil)

请帮我.如果你们有任何替代解决方案,请提出建议.

func showLoadingDialog(show : Bool)  {
        if show {
            if self.alert == nil{
                self.alert = UIAlertController(title: nil,preferredStyle: .alert)
                let loadingInDicator = UIActivityInDicatorView(frame: CGRect(x: 10,height: 50))
                loadingInDicator.hidesWhenStopped = true
                loadingInDicator.activityInDicatorViewStyle = UIActivityInDicatorViewStyle.gray
                loadingInDicator.startAnimaTing()
                self.alert.view.addSubview(loadingInDicator)
            }
            if !self.alert.isBeingPresented {
                 self.present(self.alert,completion: nil)
            }

        }else{
            self.alert.dismiss(animated: false,completion: nil)
        }
    }