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

This is documented behavior.

Swift subclasses do not inherit their superclass initializers by default

For example, following code does not even compile, because Child does not inherit init(id:String) automatically. This mechanism make sure name in Child class properly initialized.

class Parent {
    var id:String
    init(id:String) {
        self.id = id
    }
}

class Child:Parent {
    var name:String
    init(id:String, name:String) {
        self.name = name
        super.init(id: id)
    }
}

var child1 = Child(id:"child1")

If you define only convenience initializers in subclass, then it automatically inherits all of its superclass designated initializers as documented in "Automatic Initializer Inheritance" section