CoreData - 一对多关系(CoreData - One-to-many relationship)

 我将发布以下代码然后解释我的斗争 
 
 此功能可以节省一天（如星期日，星期一，星期二等）： 
 
func appendDaysToArray() {
        let dayLabel = dayName.text
        daysArray.append(dayLabel)

        let dayEntity = NSEntityDescription.entityForName("TrainingDay", inManagedObjectContext: moc!)
        let trainingday = TrainingDay(entity: dayEntity!, insertIntoManagedObjectContext: moc)
        trainingday.day = dayName.text

        var error: NSError?
        moc?.save(&error)

        if let err = error {
            var status = err.localizedFailureReason
            println("\(status)")
        } else {
            println("Day #\(dayName.text) saved successfully!")
        }
    }
 
 这个节省了详细信息作为名称，一些集合和一些重复（如健身房练习）： 
 
func appendTrainingDetails () {

        let nameLabel = exerciseName.text
        namesArray.append(nameLabel)
        let numberOfSets = setsNumber.text?.toInt()
        setsArray.append(numberOfSets!)
        let numberOfReps = repsNumber.text?.toInt()
        repsArray.append(numberOfReps!)

        let detailsEntity = NSEntityDescription.entityForName("TrainingDetails", inManagedObjectContext: moc!)
        let trainingdetails = TrainingDetails(entity: detailsEntity!, insertIntoManagedObjectContext: moc)
        trainingdetails.exerciseName = exerciseName.text
        trainingdetails.setsNumber = setsNumber.text!
        trainingdetails.repsNumber = repsNumber.text!


        var error: NSError?
        moc?.save(&error)

        if let err = error {
            var status = err.localizedFailureReason
            println("\(status)")
        } else {
            println("Exercise: #\(exerciseName.text) saved successfully!")
            println("Number of sets: #\(setsNumber.text) saved successfully!")
            println("Number of reps: #\(repsNumber.text) saved successfully!")
        }
    }
 
 我的应用程序运行正常，但我真正需要的是：对于每一天，我将有多个exerciseNames，setsNumber和repsNumber。 我设置了一对多关系，但我不知道如何将daysDetails属于daysArray中的每一天。 
 
 这是我的2个型号： 
 
import Foundation
import CoreData

class TrainingDay: NSManagedObject {

    @NSManaged var day: String
    @NSManaged var relationship1: NSSet

}
 
 和 
 
import Foundation
import CoreData

class TrainingDetails: NSManagedObject {

    @NSManaged var exerciseName: String
    @NSManaged var repsNumber: String
    @NSManaged var setsNumber: String
    @NSManaged var relationship2: TrainingDay

}
 
 之后，我每天都会有一个按钮，按下后，他们会用特定日期的练习列表更新tableView。 这就是我需要设置这种一对多关系的原因。 
 
 我怎样才能做到这一点？ 
 
 对不起任何错误。 提前致谢！！ 

I'll post the following code then explain my struggle
 
This function saves a day (like sunday, monday, tuesday, etc):
 
func appendDaysToArray() {
        let dayLabel = dayName.text
        daysArray.append(dayLabel)

        let dayEntity = NSEntityDescription.entityForName("TrainingDay", inManagedObjectContext: moc!)
        let trainingday = TrainingDay(entity: dayEntity!, insertIntoManagedObjectContext: moc)
        trainingday.day = dayName.text

        var error: NSError?
        moc?.save(&error)

        if let err = error {
            var status = err.localizedFailureReason
            println("\(status)")
        } else {
            println("Day #\(dayName.text) saved successfully!")
        }
    }
 
and this one saves details as a name, a number of sets and a number of repetitions (like gym exercises):
 
func appendTrainingDetails () {

        let nameLabel = exerciseName.text
        namesArray.append(nameLabel)
        let numberOfSets = setsNumber.text?.toInt()
        setsArray.append(numberOfSets!)
        let numberOfReps = repsNumber.text?.toInt()
        repsArray.append(numberOfReps!)

        let detailsEntity = NSEntityDescription.entityForName("TrainingDetails", inManagedObjectContext: moc!)
        let trainingdetails = TrainingDetails(entity: detailsEntity!, insertIntoManagedObjectContext: moc)
        trainingdetails.exerciseName = exerciseName.text
        trainingdetails.setsNumber = setsNumber.text!
        trainingdetails.repsNumber = repsNumber.text!


        var error: NSError?
        moc?.save(&error)

        if let err = error {
            var status = err.localizedFailureReason
            println("\(status)")
        } else {
            println("Exercise: #\(exerciseName.text) saved successfully!")
            println("Number of sets: #\(setsNumber.text) saved successfully!")
            println("Number of reps: #\(repsNumber.text) saved successfully!")
        }
    }
 
My app is working ok, but what I actually need is this: for each DAY, I will have multiple exerciseNames, setsNumber and repsNumber. I set a one-to-many relationship, but I don't know how to attribute the TrainingDetails to each day in the daysArray. 
 
Here are my 2 models:
 
import Foundation
import CoreData

class TrainingDay: NSManagedObject {

    @NSManaged var day: String
    @NSManaged var relationship1: NSSet

}
 
and
 
import Foundation
import CoreData

class TrainingDetails: NSManagedObject {

    @NSManaged var exerciseName: String
    @NSManaged var repsNumber: String
    @NSManaged var setsNumber: String
    @NSManaged var relationship2: TrainingDay

}
 
Later, I'll have a button for each day and, when pressed, they will update a tableView with the list of exercises for that specific day. That's why I need to set this one-to-many relationship. 
 
How can I achieve this?
 
Sorry for any mistakes. Thanks in advance!!

原文：https://stackoverflow.com/questions/32013330