Error with Swift and Core Data: fatal error: use of unimplemented initializer 'init(entity:insertIntoManagedObjectContext:)'

Question

I have the following class that inherits from NSManagedObject:

import Foundation
import CoreData


class Note: NSManagedObject {



    @NSManag         


        

Answer 1

You must implement the following in your NSManagedObject subclass (this is the Swift 3.0 version):

@objc
private override init(entity: NSEntityDescription, insertInto context: NSManagedObjectContext?) {
    super.init(entity: entity, insertInto: context)
}

The answer is kind of answering it, but not really directly.

The reasoning for this is that Swift does not inherit their supercalls designated initializers by default AND it seems as CoreData by uses this initializer when doing fetches (insert a breakpoint in the method to see). So here we "bring up" the designated initializer for CoreData to use.

If you have NSManagedObject base classes, you must also implement this method in those.

Credits to JSQCoreDataKit for the idea.