Need to update tableView - swift

Question

I'm studying programming in Swift, and I've got this example from a book with a mistake (commented). How can I fix this and update tableView while pressing the Add button? I've read many solutions, but none seem to work. Also, tableView updated when I reloaded simulator. I've been stuck with this for two days, and it's driving me mad! :)
import UIKit
import CoreData
class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
var managedObjectContext: NSManagedObjectContext!
override func viewDidLoad() {
super.viewDidLoad()
let appDelegate: AppDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
managedObjectContext = appDelegate.managedObjectContext! as NSManagedObjectContext
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func loadBooks() -> Array<AnyObject> {
var error: NSError? = nil
var fetchRequest = NSFetchRequest(entityName: "Book")
let result: [AnyObject] = managedObjectContext!.executeFetchRequest(fetchRequest, error:&error)!
return result
}
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 1
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return loadBooks().count
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
var cell = tableView.dequeueReusableCellWithIdentifier("Cell") as! UITableViewCell
var book: Book = loadBooks()[indexPath.row] as! Book
cell.textLabel!.text = book.title
return cell
}
#IBAction func addNew(sender: AnyObject) {
let entity = NSEntityDescription.entityForName("Book", inManagedObjectContext:managedObjectContext)
var book = Book(entity: entity!,insertIntoManagedObjectContext:managedObjectContext)
book.title = "My Book:" + String(loadBooks().count)
var error: NSError?
managedObjectContext.save(&error)
myTableView.reloadData() //mistake!
}
}

Answer 1

You have to declare your an outlet for your tableview which is probably set up in the according storyboards view controller.
import UIKit
import CoreData
class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
var managedObjectContext: NSManagedObjectContext!
#IBOutlet weak var myTableView: UITableView!
// your code
}
Please don't forget to connect your table view instance from the storyboard with your new created outlet, by opening code and storyboard side-by-side and draw a line from the dot next to the outlet to the tableview.
Or you can use the way apple describes here (https://developer.apple.com/library/ios/recipes/xcode_help-IB_connections/chapters/CreatingOutlet.html) to create your outlet from the table view on the storyboard.

Answer 2

edit:
Nevermind, i realized that if you wouldnt have had connected the dataSource and delegate, the crash would have happend way before the addNew().
Kie's answer is correct, however to see an actual result you also need to connect the dataSource and delegate of the tableView to your class.
You can do this either in storyboard, or in code in the viewDidLoad method.
override func viewDidLoad(){
super.viewDidLoad()
myTableView.dataSource = self
myTableView.delegate = self
// Additional code
}