'+entityForName: nil is not a legal NSManagedObjectContext parameter - Core Data

Question

I have added all of the relevant code to the App Delegate, and I am able to add to the data model and fetch from the data model in applicationDidFinishLaunchingWithOptions.<

Answer 1

In my case the .xcdatamodeld was mislabeled in the AppDelegate:

 let container = NSPersistentContainer(name: "name of data model")

Answer 2

If the destination view controller is embedded in a NavigationController, the context needs to be set appropriately as follows-

  self.mydetailViewController = [[[segue destinationViewController] viewControllers] objectAtIndex:0];
 [self.mydetailViewController setManagedObjectContext:self.managedObjectContext];