切换到 Xcode 6 Beta 5 后，所有 IBOutlets 都变为 nil [英] All IBOutlets become nil after switching to Xcode 6 Beta 5

问题描述

例如，视图控制器中有一个属性

For instance, there is a property in a view controller

@IBOutlet weak var nameLabel: UILabel!

此属性在 viewWillAppear 和 viewDidLoad 中为 nil，因此应用程序在运行时崩溃.

This property is nil inside viewWillAppear and viewDidLoad, so the app crashes at runtime.

它在 Xcode 6 Beta 4 中运行良好.在我切换到 Beta 5 后，它抱怨控制器类 没有实现其超类的必需成员.所以我加了

It was working fine in Xcode 6 Beta 4. After I switched to Beta 5, it complained about the controller class does not implement its superclass's required members. So I added

required init(coder aDecoder: NSCoder!) {
  super.init(coder: aDecoder)
}

那个编译器错误消失了.但是，应用程序崩溃时 unexpectedly found nil while unwrapped an Optional value 因为当我尝试设置它的 时 nameLabel 属性是 nil文字.

And that compiler error disappeared. However, the app crashes for unexpectedly found nil while unwrapping an Optional value because that nameLabel property is nil when I try to set its text.

我通读了发行说明，但不知道如何解决这个问题.

I read through the release notes and could not figure out how to fix this issue.

推荐答案

我在 Beta5 中遇到了同样的问题.这似乎是一个问题

I was having the same issue in Beta5. It appears to be a problem where

init(nibName: nil, bundle: nil) 

没有将 nil 映射到默认的 nibName.当我更改为显式 nibName 时，它​​起作用了.特别是在我的情况下，使用新的 ??操作员:

is not mapping nil to the default nibName. When I changed to an explicit nibName then it worked. Specifically in my case, using the new ?? operator:

override init(nibName nibNameOrNil: String!, bundle nibBundleOrNil: NSBundle!) {
   // beta5 workaround: replace nil with explicit name of xib file
   let nib = nibNameOrNil ?? "MyViewController"

   super.init(nibName: nib, bundle: nibBundleOrNil)

   // local initialization here
}

让它再次神奇地工作.

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