ios DestinationViewController Segue 和 UINavigationController swift
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DestinationViewController Segue and UINavigationController swift
提问by YichenBman
So I have a prepareForSegue method like this:
所以我有一个像这样的 prepareForSegue 方法：
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "fromEventTableToAddEvent" {
let addEventViewController: AddEventViewController = segue.destinationViewController as! AddEventViewController
addEventViewController.newTagArray = newTagArray
}
}
However, at runtime the app crashes and logs spit out this message:
但是，在运行时，应用程序崩溃并在日志中输出以下消息：
Could not cast value of type 'UINavigationController'
无法转换“UINavigationController”类型的值
The error comes because the addEventController is embedded in a navigation controller, however I'm not sure how I would set up the segue so that the destinationViewController is set to the NavigationController, but also allow me to pass variables in the prepareForSegue method to the addEventController
出现错误是因为 addEventController 嵌入在导航控制器中，但是我不确定如何设置 segue 以便将 destinationViewController 设置为 NavigationController，但也允许我将 prepareForSegue 方法中的变量传递给 addEventController
So how would I do this using Swift?
那么我将如何使用 Swift 做到这一点呢？
I extremely appreciate your help and time you may offer in response. It helps alot
我非常感谢您提供的帮助和时间作为回应。它有很大帮助
回答by rdelmar
You only need to access the navigation controller's topViewController, which will be the AddEventViewController. Here is the code:
您只需要访问导航控制器的 topViewController，即 AddEventViewController。这是代码：
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "fromEventTableToAddEvent" {
let nav = segue.destinationViewController as! UINavigationController
let addEventViewController = nav.topViewController as! AddEventViewController
addEventViewController.newTagArray = newTagArray
}
}
