类型“Int”不符合协议“NSCopying”答案

【问题标题】：Type 'Int' does not conform to protocol 'NSCopying'类型“Int”不符合协议“NSCopying”
【发布时间】：2015-08-08 16:45:41
【问题描述】：

我正在使用这个Custom Collection View Layout 实现。我可以很好地运行该 repo 中的示例，但是当我将 CustomCollectionViewLayout.swift 复制到我自己的项目中时，我在方法上收到 Type 'Int' does not conform to protocol 'NSCopying' 错误

override func layoutAttributesForItemAtIndexPath(indexPath: NSIndexPath) -> UICollectionViewLayoutAttributes? {
    return self.itemAttributes[indexPath.section][indexPath.row] as? UICollectionViewLayoutAttributes
}

其中var itemAttributes 是NSMutableArray!

第二个索引[indexPath.row]正在生成错误。

有什么想法吗？我尝试将相同的功能放在一个快速的操场上，并没有收到任何错误..

更新！ This 是一个 swiftstub，其中保存了我的游乐场。由于Import UIKit，它没有执行，但以下原因：

let x = collectionViewLayout.itemAttributes[indexPath.section]
let y = collectionViewLayout.itemAttributes[indexPath.section][indexPath.row]
print( "x's type = \(_stdlib_getDemangledTypeName(x))")
print("x = \(x)")
print( "y's type = \(_stdlib_getDemangledTypeName(y))")
print("y = \(y)")

产量：

x's type = __NSArrayM
x = (
    "<UICollectionViewLayoutAttributes: 0x7fbe6ac041d0> index path: (<NSIndexPath: 0xc000000000000016> {length = 2, path = 0 - 0}); frame = (0 0; 66 30); zIndex = 1024; ",
    "<UICollectionViewLayoutAttributes: 0x7fbe6ac05030> index path: (<NSIndexPath: 0xc000000000200016> {length = 2, path = 0 - 1}); frame = (65 0; 63 30); zIndex = 1023; ",
    "<UICollectionViewLayoutAttributes: 0x7fbe6ae1e2a0> index path: (<NSIndexPath: 0xc000000000400016> {length = 2, path = 0 - 2}); frame = (127 0; 65 30); zIndex = 1023; ",
    "<UICollectionViewLayoutAttributes: 0x7fbe6ac06830> index path: (<NSIndexPath: 0xc000000000600016> {length = 2, path = 0 - 3}); frame = (191 0; 66 30); zIndex = 1023; ",
    "<UICollectionViewLayoutAttributes: 0x7fbe6ae21e50> index path: (<NSIndexPath: 0xc000000000800016> {length = 2, path = 0 - 4}); frame = (256 0; 67 30); zIndex = 1023; ",
    "<UICollectionViewLayoutAttributes: 0x7fbe6ad70f30> index path: (<NSIndexPath: 0xc000000000a00016> {length = 2, path = 0 - 5}); frame = (322 0; 66 30); zIndex = 1023; ",
    "<UICollectionViewLayoutAttributes: 0x7fbe6ac054e0> index path: (<NSIndexPath: 0xc000000000c00016> {length = 2, path = 0 - 6}); frame = (387 0; 66 30); zIndex = 1023; ",
    "<UICollectionViewLayoutAttributes: 0x7fbe6ad72420> index path: (<NSIndexPath: 0xc000000000e00016> {length = 2, path = 0 - 7}); frame = (452 0; 65 30); zIndex = 1023; "
)
y's type = Swift.ImplicitlyUnwrappedOptional<Swift.AnyObject>
y = <UICollectionViewLayoutAttributes: 0x7fbe6ac041d0> index path: (<NSIndexPath: 0xc000000000000016> {length = 2, path = 0 - 0}); frame = (0 0; 66 30); zIndex = 1024;

【问题讨论】：

如果将self.itemAttributes[indexPath.section]保存到变量中，Swift认为它的类型是什么？
@PhillipMills 我更新了我的问题。这在操场上工作但在我的编辑器中无法编译，这并不奇怪吗？
您使用的是哪个版本的 XCode？span>
我也有同样的错误。将不胜感激任何帮助。
Xcode 7 beta-4 @codecowboy

标签： swift nsmutablearray uicollectionviewlayout swift2 nscopying

【解决方案1】：

把override func layoutAttributesForItemAtIndexPath改成

override func layoutAttributesForItemAtIndexPath(indexPath: NSIndexPath) -> UICollectionViewLayoutAttributes? { let row = indexPath.row let x : NSMutableArray = self.itemAttributes[indexPath.section] as! NSMutableArray let l = x[row] as? UICollectionViewLayoutAttributes return l }

我将在今天晚些时候 fork CustomCollectionLayoutView 并制作一个 swift2 副本

【讨论】：

请您解释一下为什么会修复它？