如何在swift中關閉第二個viewcontroller后啟用帶有視圖的customview控制器

Question

我有兩個視圖控制器imag 1.第一個視圖控制器是主要的，第二個是CustomAlertviw控制器主視圖控制器就像上面的圖像，當我點擊繼續顯示customalertview控制器，就像圖像一樣。 當點擊輸入pin按鈕時我必須關閉視圖控制器並在主視圖控制器上顯示帶有uiview的視圖控制器但是嘗試了，它顯示了視圖控制器，還有一個自定義視圖沒有顯示它崩潰我的應用程序

主視圖代碼

    @IBAction func backButtonClicked(_ sender: UIButton) {

    let myAlert = UIStoryboard(name: "CustomAlertview", bundle: nil).instantiateViewController(withIdentifier: "CustomAlertViewController") as? CustomAlertViewController
            myAlert?.modalPresentationStyle = UIModalPresentationStyle.overCurrentContext
            myAlert?.modalTransitionStyle = UIModalTransitionStyle.crossDissolve
         self.present(myAlert!, animated: true, completion: nil)

}

Customalertview controller 
  @IBAction func enterPinButtonClick(_ sender: Any) {

       self.dismiss(animated: true, completion: nil)
        let myAlert = UIStoryboard(name: "ScanAndPay", bundle: nil).instantiateViewController(withIdentifier: "ScanAndPayDetailsEntryViewController") as? ScanAndPayDetailsEntryViewController
        myAlert?.modalPresentationStyle = UIModalPresentationStyle.overCurrentContext
        myAlert?.modalTransitionStyle = UIModalTransitionStyle.crossDissolve
        self.present(myAlert!, animated: true, completion: nil)
        myAlert.valuespass()
    }


inside main view controller one function calling from the customalrerview 

func  valuespass()
    {
        DispatchQueue.main.async {
            self.authType = 1
            self.authStatus = false
            print("this is calling")
            self.pinStatusLabel.text = "Please enter a 4-digit Security PIN"
}

當我從自定義警報視圖應用程序調用此函數時崩潰並顯示hread 1：致命錯誤：在解開Optional值時意外發現nil此錯誤。 如何在解除自定義視圖控制器后顯示所有信息。

Answer 1

你差不多完成了。 從FirstView呈現ScanAndPay而不是CustomAlertview 。

我已經完成了使用Delegate因為我認為它適合這種情況。 按照以下步驟 -

第1步：

在FirstViewController中 ，

添加 - CustomAlertviewDelegate這樣的事情 -

  class FirstViewController: UIViewController, CustomAlertviewDelegate {

現在替換你的backButtonClicked方法 -

  @IBAction func backButtonClicked(_ sender: UIButton) {

        let myAlert = UIStoryboard(name: "CustomAlertview", bundle: nil).instantiateViewController(withIdentifier: "CustomAlertViewController") as? CustomAlertViewController
        myAlert?.modalPresentationStyle = UIModalPresentationStyle.overCurrentContext
        myAlert?.modalTransitionStyle = UIModalTransitionStyle.crossDissolve
        myAlert.delegate = self
        self.present(myAlert!, animated: true, completion: nil)

  }

添加CustomAlertviewDelegate的新Delegate方法 -

func ScanAndPayView(){
       DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
           let myAlert = UIStoryboard(name: "ScanAndPay", bundle: nil).instantiateViewController(withIdentifier: "ScanAndPayDetailsEntryViewController") as? ScanAndPayDetailsEntryViewController
           myAlert?.modalPresentationStyle = UIModalPresentationStyle.overCurrentContext
           myAlert?.modalTransitionStyle = UIModalTransitionStyle.crossDissolve
           self.present(myAlert!, animated: true, completion: nil)
    }
}

第2步：

現在是CustomAlertview的時間，

為類的頂級添加協議 -

protocol CustomAlertviewDelegate: class {

   func ScanAndPayView()
}

class CustomAlertview: UIViewController{
  weak var delegate : CustomAlertviewDelegate!
  ...
  override func viewDidLoad() { // Rest of your code
}

現在是時候關閉當前視圖控制器並通知FirstViewController呈現ScanAndPay view Controller -

@IBAction func enterPinButtonClick(_ sender: Any) {
   delegate.ScanAndPayView()
   self.dismiss(animated: true, completion: nil)

}

希望它能幫助你實現你想要的。