How to Save Value in Nsset Core Data (Swift)

How to save value in NSSet Core Data (Swift)

It's always easier to do it from the other end:

employees.company = company

Core data will take care of the many side of the relationship because you've specified the inverse relationship in your data model.

Also, rename your entity. It should be called Employee, since each entity represents one employee. It will save you a lot of confusion down the road.

If you really insist on editing it from the company end, you do it like this:

company.mutableSetValueForKey("employees").addObject(employees)

Which I hope you'll agree is significantly uglier and more prone to errors.

How to use NSSet created from Core Data

Core Data supports widely native Swift types.

Declare codes as Set<Codes> in the Person class.

It's much more convenient than typeless NSSet.

You get a strong type and you can apply all native functions like filter, sort, etc. without type cast.

SwiftUI - Saving ARRAY into NSSet

Try the following instead of that line

if let categories = newQuestion.categories {
    newQuestion.categories = categories.addingObjects(from: self.selections)
} else {
    newQuestion.categories = Set(self.selections)
}

Why can't I save NSSet to 'to-many' relationship in coredata?

The most likely cause of this error as you report it is trying to add a set of the wrong class of objects. You can only add objects of the entity/class that is defined for the relationship in the data model.

So, if you have a data model like this:

Family{
    name:string
    people<-->>Person.family
}

Person{
    name:string
    family<<-->Family.people
}

... and you have NSManagedObject subclasses of FamilyMO and PersonMO, then you can only assign a set of PersonMO objects to the Family.people relationship. If you tried to assign a set like this:

NSSet *badSet=[NSSet setWithObjects:PersonMO1, PersonMO2, FamilyMO1, PersonMO2,nil];
aFamilyMO.people=badSet;

... it would fail and IIRC, it would do so silently.

Convert NSSet into an Array

My suggestion is to declare the relationship as non-optional native Swift type

@NSManaged public var children: Set<Node>

To get an array just sort the set. This is pretty easy with a Swift Set. As a set is unordered by definition you have to do that anyway to get a fixed order. Assuming you have a dateAdded attribute you can write

let sortedChildren = children.sorted{$0.dateAdded > $1.dateAdded}

How to add to an NSSet using Core Data in Swift 5

When you add a relationship to an entity Xcode creates methods for getting and setting values for that relationship using a pre-defined naming standard. So you should have some methods in your Pokemon class for setting Type instances (and code completion should be able to help here):

addToTypes(value:) // single object
addToTypes(values:) //set of objects

So in your code it should be

pokemon.addToTypes(value: type)

You also have the same methods on Type for the opposite direction

Core Data relationship, NSSet & ManagedObjectContext

The usual way to get the members of the Set object as array is the method allObjects, but apart from that you cannot cast the TaskEntity object to String.

...
if let tasksArray = employeeRecord.tasks?.allObjects as? [TaskEntity] where !tasksArray.isEmpty {
    cell.task1Label.text = tasksArray[0].taskName
    cell.task1Label.text = tasksArray[1].taskName // or is it cell.task2Label ??
    print(tasksArray[0].status)
}

return cell

Consider to rename the Core Data entities and their attributes. Actually the NSManagedObject subclasses represent always an entity so it's redundant to include Entity in the name. Or the attribute taskName in TaskEntity could be just name. While reading the code you can infer that name belongs to Task

Regarding the status property you need to create an Int32 attribute statusValue in the Task entity to store the value in Core Data. The code to map the enumeration to Int32 and vice versa is fine.

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