ios - Swift 二维数组扩展

Question

我正在尝试对 Array 类型进行扩展，以便能够使用 2D 数组。事实上，我是在 Objective-C 中完成的，下面的代码非常有效。但我真的坚持使用 Swift。

extension Array {
    mutating func addObject(anObject : AnyObject, toSubarrayAtIndex idx : Int) {
        while self.count <= idx {
            let newSubArray = [AnyObject]()
            self.append(newSubArray)
        }

        var subArray = self[idx] as! [AnyObject]
        subArray.append(anObject)
    }

    func objectAtIndexPath(indexPath : NSIndexPath) -> AnyObject {
        let subArray = self[indexPath.section] as! Array
        return subArray[indexPath.row] as! AnyObject
    }
}

无论我做什么我都会得到这个错误:

Error: Cannot invoke 'append' with an argument list of type '([AnyObject])'

如果有任何帮助，我将不胜感激。

Answer 1

@brimstone 的答案很接近，但如果我正确理解你的问题，它是一个 [AnyObject] 数组，这意味着它应该如下所示:

extension Array where Element: _ArrayType, Element.Generator.Element: AnyObject {
    mutating func addObject(anObject : Element.Generator.Element, toSubarrayAtIndex idx : Int) {
        while self.count <= idx {
            let newSubArray = Element()
            self.append(newSubArray) // ERROR: Cannot invoke 'append' with an argument list of type '([AnyObject])'
        }

        var subArray = self[idx]
        subArray.append(anObject)
    }

    func objectAtIndexPath(indexPath: NSIndexPath) -> AnyObject {
        let subArray = self[indexPath.indexAtPosition(0)]
        return subArray[indexPath.indexAtPosition(1)] as Element.Generator.Element
    }
}