Swift，集合视图&故事板，在另一个标签上使用 viewWithTag 时获得 null [英] Swift, collection view & storyboard, get null when using viewWithTag on another Label

问题描述

我看到了一些非常奇怪的行为，我需要一些帮助.我有一个最初有一个标签的集合视图单元格，标签为 43.

I am seeing some extremely odd behavior that I would like some assistance with. I have a collection view cell that originally had one label, with a tag of 43.

我正在使用以下代码设置标签的值:

I am setting the value of the label using the following code:

func collectionView(collectionView: UICollectionView!, cellForItemAtIndexPath indexPath: NSIndexPath!) -> UICollectionViewCell! {
    let object = self.fetchedResultsController.objectAtIndexPath(indexPath) as NSManagedObject
    let cell = collectionView.dequeueReusableCellWithReuseIdentifier("playerCell", forIndexPath: indexPath) as UICollectionViewCell
    cell.backgroundColor = UIColor.orangeColor()
    let mintmplabel : UILabel = cell.viewWithTag(43) as UILabel
    mintmplabel.text = "fruktkaka"
    //(cell.viewWithTag(43) as UILabel).text =  object.valueForKey("playerName").description
    //let mintmplabelb : UILabel = cell.viewWithTag(41) as UILabel
    //mintmplabelb.text = "megaman"
    //(cell.viewWithTag(41) as UILabel).text =  object.valueForKey("playerName").description


    return cell
}

它按预期工作！但是，我后来尝试在集合视图单元格中添加另一个标签，并将其标记为 41.当我取消注释行时

It works as expected! However, I later tried to add another label to the collection view cell, and give it a tag of 41. When I uncomment the lines

    //let mintmplabelb : UILabel = cell.viewWithTag(41) as UILabel
    //mintmplabelb.text = "megaman"

我收到以下错误(在let"行):

I get the following error (on the "let" line):

致命错误:在展开可选值时意外发现 nil(lldb)

fatal error: unexpectedly found nil while unwrapping an Optional value (lldb)

源代码中显示当前消息:Thread 1: EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, sub code =0x0)"

The current message is shown in the source code: "Thread 1: EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, sub code =0x0)"

我尝试了许多不同的方法，但我就是无法让它发挥作用.我还尝试删除两个标签，并重新添加它们(使用相同的标签).这打破了标签 43 和 41 的标签！

I have tried many different approaches, but I just can not get it to work. I have also tried to remove both labels, and re-add them (with the same tags). That breaks both the label with tag 43 and 41!

要么我在如何使用标签方面遗漏了一些东西，要么我偶然发现了某种错误.

Either I am missing something on how to use tags, or I have stumbled upon some kind of bug.

我使用的是 Xcode 6 beta 5.

I am using Xcode 6 beta 5.

任何帮助将不胜感激，我不知道去哪里寻找更多信息.

Any help will be greatly appreciated, I do not know where to look for more information.

谢谢/马丁

推荐答案

好吧，看来在这里提出问题让我找到了答案.. 我不知道它为什么有效，但确实有效.

Okay, so it seems that asking a question here makes me find the answer.. I do not know why it worked, but it did.

我选择了无效的标签，在故事板属性检查器"中，未选中已安装"复选框，并选中了已安装 wC hR"复选框.通过取消选中已安装 wC hR"并选中已安装"复选框，它又开始工作了.

I selected the label that did not work, and in the Storyboard "attribute inspector", a checkbox that said "Installed" was unchecked, and underneath a checkbox that said "wC hR Installed" was checked. By unchecking the "wC hR installed" and checking the "installed" checkbox, it began to work again.

我不知道这是做什么的，如果我发现会更新答案.

I have no idea what this does, will update the answer if I find out.

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