How to create and store managed objects containing data using Swift 3.0 in Xcode 8.2

Question

I get the error message "use of unresolved identifier" Contacts "(this is the name that I named Entity in my" fileName.xcdatamodeld ").

import UIKit
import CoreData

class ViewController: UIViewController {

    let managedObjectContext = (UIApplication.shared.delegate as! AppDelegate).persistentContainer.viewContext         
   override func viewDidLoad() {
        super.viewDidLoad()         
    }
    @IBAction func SaveContact(_ sender: Any) {
        let entityDescription = NSEntityDescription.entity(forEntityName: "Contacts",in: managedObjectContext)

        let contact = Contacts(entity: entityDescription!,insertInto: managedObjectContext) // Error: Use of unresolved identifier 'Contacts'
    }
    @IBAction func Findcontact(_ sender: Any) {
    }
   }

Answer 1

Here's how you set up Core Data in Xcode 8:

You have 3 options:

• Manual / no
• Class definition
• Category / Extension

I think they are pretty clear. Anyway, what you probably want here is a class definition.