排序这与CoreData填充数组 [英] Sorting an array that's filled from CoreData

问题描述

我有哪些用户可以输入数值，并将它们存储到核心数据作为字符串文本字段。反过来，我检索这些值，并存储它们放入数组为整数。我想要做的排序是该阵列由用户，因为我试图绘制的值，看看随着时间的推移其走势存储值的顺序。眼下值从所有我可以告诉填充在一个完全随机的方式我的图表。

I have a text field in which users can input numerical values and store them to core data as strings. In turn I am retrieving those values and have stored them in an array as ints. What I want to do is sort that array by the order that the user stores the values because I am trying to graph the values to see their trend over time. Right now the values are populating my graph in a totally random manner from all I can tell.

var client: Client! = nil
var weights = []

func getWeights() {
        var assessmentWeights: NSSet = client.assessment.valueForKey("weight") as NSSet
        var weightSet: NSSet = assessmentWeights.valueForKey("integerValue") as NSSet
        weights = weightSet.allObjects
        println(weights)
    }

任何帮助AP preciated！ ：）

Any help is appreciated! :)

推荐答案

如果您已经在各权重项，你可以（一）建立关联的时间戳的 NSFetchRequest 与排序描述符，也可以（b）以的NSSet

If you already have a timestamp associated with each weight entry you can either (a) create a NSFetchRequest with sort descriptor or you can (b) sort the values you already have in NSSet

由于我没有看到太多code一起去，这里的选项的示例（二）：

Since I do not see much code to go with, here's an example of option (b):

var weights = [Int]();
if let entries = client.assessment.allObjects as? [Assessment] {
    let sorted = entries.sorted {
        return $0.timestamp.compare($1.timestamp) == .OrderedAscending
    }
    for assessment in sorted {
        if let intValue = assessment.weight.toInt() {
            weights.append(intValue)
        }
    }
}

return weights

话虽如此，最好的选择，在我看来，是权重值存储为一个数值并使用 NSFetchRequest （结果类型。 DictionaryResultType ）与时间戳排序描述得到你想要的值。

Having said this, the best option, in my opinion, is to store weight value as a numeric value and use NSFetchRequest (result type .DictionaryResultType) with sort descriptor on timestamp to get the values you want.

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