無法實例化View Controller

Question

我有一個函數，通過它可以檢查是否設置了UserDefaults，如果沒有，則打開一個新的View Controller並顯示一個登錄屏幕，該屏幕將設置用戶默認值。

我的問題是視圖控制器沒有實例化，但是我得到打印“用戶未注冊”

func checkUserAccount() {
        let defaults = UserDefaults.standard
        let accountName = defaults.bool(forKey: "PUserAccountName")
        let accountPassword = defaults.bool(forKey: "PUserAccountPassword")
        if accountName == true && accountPassword == true  {
            print("User Registered")

        } else {

            let storyboard: UIStoryboard = UIStoryboard(name: "PolTRiM", bundle: nil)
            let vc: StudentLoginVC  = storyboard.instantiateViewController(withIdentifier: "studentLogin") as! StudentLoginVC
            vc.modalPresentationStyle = .custom
            vc.modalTransitionStyle = .crossDissolve
            self.present(vc, animated: true, completion: { _ in })
            print("User not registered")
        }

    }

有什么想法嗎？

Answer 1

您是否仔細檢查過UIStoryBoard名稱和UIViewController標識符（如果編寫正確）？ 否則這段代碼對我有用

let storyboard = UIStoryboard(name: "Main", bundle: nil)
let viewController = storyboard.instantiateViewController(withIdentifier :"MyViewController") as! UIViewController
self.present(viewController, animated: true)