有没有一种方法可以按添加对象的时间顺序对核心数据进行排序? [英] Is there a way to keep the sorting in core data in the time order the objects are added?

问题描述

如果我只是将模拟的data添加到coreData中，如下所示:

If I just add mocked data to coreData like this:

func mockData() {´
    let entity = NSEntityDescription.entity(forEntityName: "LocalDoorCoreDataObject", in: context)

    for i in 1...3 {
        var myEntity = MyCoreDataObject(entity: entity!, insertInto: context)
        myEntity.dName = "MOCKED NAME \(i)"
        }
    }

但是当我fetch data时，它不是按1、2、3顺序排列的，而是随机列出的.有没有一种方法可以完全按照store到coreData的顺序来store和fetch data?这很重要，因为我希望能够通过将cells的顺序拖到另一个位置，然后将更改存储到coreDatabase来重新排列.

But when I fetch the data it's not ordered 1, 2, 3, but is rather listed randomly. Is there a way to store and fetch the data exactly in the order you store it to the coreData? This is important since I want to be able to rearrange the order of the cells by dragging them to a different place, then storing the changes to coreDatabase.

推荐答案

1. 在NSManagedObject子类中添加一个属性(当然也在模型中)

1. In the NSManagedObject subclass add an attribute (of course also in the model)

@NSManaged var itemAdded : Date

覆盖awakeFromInsert

override func awakeFromInsert() {
    super.awakeFromInsert()
    itemAdded = Date()
}

现在您可以按itemAdded

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