ios - 尝试在 Swift 中使用警报操作切换到另一个 View Controller

Question

在我的代码中，我有一个允许用户登录或注册的操作表。当用户按下其中任何一个时，我想定义一个处理程序，将它们连接到登录/注册 View Controller 。我对此很陌生，所以我不太确定我做错了什么，但在我的代码中我收到一个错误，指出类型不可转换。代码如下所示:

let actionSheet = UIAlertController(title: "Do you have an account?", message: "Please Log-In or Sign-Up", preferredStyle: .ActionSheet)
    if let presentationController = actionSheet.popoverPresentationController {
        presentationController.sourceView = sender as UIView
        presentationController.sourceRect = sender.bounds
    }

    let dismissHandler = {
        (action: UIAlertAction!) in
        self.dismissViewControllerAnimated(true, completion: nil)
    }
    let signupHandler = ({
        (ViewController: UIViewController!) in
        let signupVC: nextViewController = segue.signupVC as nextViewController
    })
    let loginHandler = ({
        (ViewController: UIViewController!) in
        let loginVC: nextViewController = segue.loginVC as nextViewController
    })
    actionSheet.addAction(UIAlertAction(title: "Cancel", style: .Cancel, handler: dismissHandler))
    actionSheet.addAction(UIAlertAction(title: "Log-In", style: .Default, handler: dismissHandler))
    actionSheet.addAction(UIAlertAction(title: "Sign-Up", style: .Default, handler: signupHandler))
    presentViewController(actionSheet, animated: true, completion: nil)

}

任何帮助将不胜感激!提前致谢。

Answer 1

我不知道 segues 但我通常只是像这样展示它们:

let loginVC = LoginViewController()
self.presentViewController(loginVC, animated: true, completion: nil)