Swift 3.0 中的 UIAlertAction 中的 UIAlertView？

Question

是否可以在 UIAlertAction 中添加 UIAlert 视图？

因为当我尝试在 UIAlertAction 中添加 UIAlert 视图时，它说

"Warning: Attempt to present on whose view is not in the window hierarchy!"

这是我的代码。

let myAlert = UIAlertController(title: "Title", message: "title here", preferredStyle: UIAlertControllerStyle.alert)
let okaction = UIAlertAction(title: "Okay", style: UIAlertActionStyle.default, handler:
    {
        action in
        let myViewController:ViewController = self.storyboard!.instantiateViewController(withIdentifier: "ViewController") as! ViewController

        let appDelegate = UIApplication.shared.delegate as! AppDelegate
        let navigationController = UINavigationController.init(rootViewController: myViewController)
        appDelegate.window?.rootViewController = navigationController
        appDelegate.window?.makeKeyAndVisible()

        if (statement here == 1) {
            let myAlert = UIAlertController(title: "Title", message: "title", preferredStyle: UIAlertControllerStyle.alert)
            myAlert.addAction(UIAlertAction(title: "Okay", style: UIAlertActionStyle.default, handler: nil))
            self.present(myAlert, animated: true, completion: nil)
            return
        }
    }
)
myAlert.addAction(okaction)
self.present(myAlert, animated: true, completion: nil)

Answer 1

尝试将对第二个警报的调用包装在一个函数中，然后调用该函数。

像这样。

let myAlert = UIAlertController(title: "Title", message: "title here", preferredStyle: UIAlertControllerStyle.alert)
let okaction = UIAlertAction(title: "Okay", style: UIAlertActionStyle.default, handler: { action in

    let myViewController:ViewController = self.storyboard!.instantiateViewController(withIdentifier: "ViewController") as! ViewController

    let appDelegate = UIApplication.shared.delegate as! AppDelegate
    let navigationController = UINavigationController.init(rootViewController: myViewController)
    appDelegate.window?.rootViewController = navigationController
    appDelegate.window?.makeKeyAndVisible()

    if (statement here == 1) {
        self.callAlert()
    }
})

myAlert.addAction(okaction)
self.present(myAlert, animated: true, completion: nil)

func callAlert() {
    let myAlert = UIAlertController(title: "Title", message: "title", preferredStyle: UIAlertControllerStyle.alert)
    myAlert.addAction(UIAlertAction(title: "Okay", style: UIAlertActionStyle.default, handler: nil))
    self.present(myAlert, animated: true, completion: nil)
}

Answer 2

尝试在 navigationController 上展示 AlertController。

换行

self.present(myAlert, animated: true, completion: nil)

与

navigationController.present(myAlert, animated: true, completion: nil)

Swift 3.0 中的 UIAlertAction 中的 UIAlertView？

UIAlertView inside UIAlertAction in Swift 3.0 ?

appdelegate

uialertcontroller

uialertaction

swift3