Question

quickFilterDictionary中self.preferencesListFilterDictionary的第二个对象是nil。如何在NSIndexPath中添加[NSNumber]索引路径（作为键）和Dictionary（作为值）？

注意：第一个对象成功添加，当我在控制台中打印nil时，只有第二个对象为self.preferencesListFilterDictionary。我可以知道，我在下面的代码中做错了什么？

self.preferencesListFilterDictionary["price"] = 1000
self.quickFilterArr = [localizedStrOf("deliveryNowOnly"),localizedStrOf("rated")]
var quickFilterDictionary = Dictionary<NSIndexPath, NSNumber?>()
        for obj in self.quickFilterArr {
            let row = self.quickFilterArr.indexOf(obj)
            let indexPath = NSIndexPath(forRow:row!, inSection: 0)
            quickFilterDictionary[indexPath] = NSNumber(bool: false)
        }
        print(quickFilterArr.count)
        print(quickFilterDictionary)
self.preferencesListFilterDictionary.updateValue(quickFilterDictionary as? AnyObject, forKey: "quickFilterDictionaryKey")
print(self.preferencesListFilterDictionary)

控制台打印：

▿ [1] : 2 elements
    - .0 : "quickFilterDictionaryKey"
    - .1 : nil

为了从数字上面获取字典bool，我写了下面的代码 -

func getQuickFilterValueOfIndexpath(indexPath:NSIndexPath) -> Bool {
        if let val = self.preferencesListFilterDictionary["quickFilterDictionaryKey"] {
            // now val is not nil and the Optional has been unwrapped, so use it
            let tempDict = val as! Dictionary<NSIndexPath, NSNumber?>
            if let boolVal = tempDict[indexPath] {
                return boolVal!
            }
        }

        return false
    }

Answer 1

我认为你对Row，IndexPath和Index之间的区别感到困惑。

在以下代码中：

let row = self.quickFilterArr.indexOf(obj)

如果您选择单击行，您将看到它是Array.Index?类型的对象。这不是一排。

还有一个原因是你使用NSNumber，NSIndexPath和更新密钥值？与Number，IndexPath相反，只需使用以下内容更新字典值： preferencesListFilterDictionary [“quickFilterDictionaryKey] = quickFilterDictionary

如果您选择单击quickFilterArr并且它是一个IndexPaths数组[IndexPath] - 要在您所选择的索引中引用IndexPath，您可以这样做：

if let arrayIndex = quickFilterArr.indexOf(obj) {
//if your array is an array of Index Paths
//you would then pull the IndexPath object at the index you have defined above
  let indexPath = quickFilterArr[arrayIndex]
  quickFilterDictionary[indexPath] = Number(bool: false)
}

将NSIndexPath作为键和NSNumber添加为Dictionary中的值的问题？

1 个答案: