CoreData在斯威夫特阵列 [英] CoreData to Array in Swift

问题描述

我想从CoreData获取数据并返回它作为一个流行的图表库图表的数组。下面的code运行良好，我可以打印数据到控制台，但是我想，以填补在CoreData项self.hkdataBase并将其返回。任何知道我做错了？

 类的ViewController：UIViewController的{
变种hkdataBase = [HKdataBase]（）
 

...

  FUNC fetchCoreData（） -  GT; NSArray的{//设置核心数据
    VAR上下文=（UIApplication.sharedApplication（）。委托作为AppDelegate中）.managedObjectContext！
    VAR请求= NSFetchRequest（的entityName：HKdataBase）
    request.returnsObjectsAsFaults = FALSE//获取数据
    self.hkdataBase = context.executeFetchRequest（请求错误：无）！为[HKdataBase]
    如果hkdataBase.count＆GT; 0 {
        因为我在hkdataBase {        **我要填写self.hkdataBase与I元素：**  - ＆GT;的println（i.hr_data）工作正常
        }
    }其他{
        的println（无结果）
    }
}
**的元素返回self.hkdataBase **
}
 

更新1：
我想从CoreData所取得的数据返回数组。该hr_data是心率措施和hr_date是相关的NSDate。该HKdataBase看起来是这样的：

进口基金会
进口CoreData

类HKdataBase：NSManagedObject {

  @NSManaged VAR hr_date：NSDate的
@NSManaged VAR hr_data：NSNumber的
 

}

解决方案

在抓取，你已经在 self.hkdataBase 你的管理对象。管理的对象是KVC兼容的，因此要获得只是一个样的价值，如果它是很简单的。

  VAR HRDATA =（self.hkdataBase为NSArray的）.valueForKey（hr_data）作为NSArray中
 

您现在拥有一个包含hr_data一个数组，presumably 的NSNumber 对象的数组。

I am trying to fetch data from CoreData and return it as an array for charting in a popular charting library. The code below runs fine and I can print the data to the console, however I want to fill self.hkdataBase with the entries within CoreData and Return it. Any idea what I am doing wrong ?

class ViewController: UIViewController {
var hkdataBase = [HKdataBase]()

....

func fetchCoreData () -> NSArray {

//Setting up Core Data
    var context = (UIApplication.sharedApplication().delegate as AppDelegate).managedObjectContext!
    var request = NSFetchRequest(entityName: "HKdataBase")
    request.returnsObjectsAsFaults = false

//Fetching Data
    self.hkdataBase = context.executeFetchRequest(request, error: nil)! as [HKdataBase]
    if hkdataBase.count > 0 {
        for i in hkdataBase {

        **I WANT TO FILL self.hkdataBase WITH i ELEMENTS HERE **  ->  println(i.hr_data) WORKS FINE


        }
    } else {
        println("No results")
    }
}
**return self.hkdataBase with elements**
}

UPDATE 1: I want to Return an Array from the fetched data in CoreData. The hr_data are Heart Rate measures and hr_date are the associated NSDate. The HKdataBase looks like this:

import Foundation import CoreData

class HKdataBase: NSManagedObject {

@NSManaged var hr_date: NSDate
@NSManaged var hr_data: NSNumber

}

解决方案

After the fetch, you already have your managed objects in self.hkdataBase. Managed objects are KVC compliant, so to get just one kind of value out if it is quite simple.

var hrData = (self.hkdataBase as NSArray).valueForKey("hr_data") as NSArray

You now have an array containing your hr_data, presumably an array of NSNumber objects.

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