Error when trying to save Core Data objects - ios

Question

I have been trying to set up, what seems like it should be, a simple app that allows a user to update a food item with a price and store where the price was found. The main issue I know is trying to blend Swift with Objective-C even though Apple hasn't worked out the kinks yet for Swift and it's ever changing.
Anyways I have set up my AllowedTableViewController as follows
class AllowedTableViewController: UITableViewController {
var myAllowedList : Array<AnyObject> = []
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewDidAppear(animated: Bool) {
let appDel: AppDelegate = UIApplication.sharedApplication().delegate as AppDelegate
let context: NSManagedObjectContext = appDel.managedObjectContext!
let freq = NSFetchRequest(entityName: "FoodAllowed")
myAllowedList = context.executeFetchRequest(freq, error: nil)!
tableView.reloadData()
}
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "update" {
var indexPath: NSIndexPath = self.tableView.indexPathForSelectedRow()!
var selectedItem: NSManagedObject = myAllowedList[indexPath.row] as NSManagedObject
let IVC: AllowedViewController = segue.destinationViewController as AllowedViewController
IVC.name = selectedItem.valueForKey("name")as String
IVC.store = selectedItem.valueForKey("store")as String
IVC.price = selectedItem.valueForKey("price")as String
IVC.existingItem = selectedItem
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
// MARK: - Table view data source
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
// #warning Potentially incomplete method implementation.
// Return the number of sections.
return 1
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// #warning Incomplete method implementation.
// Return the number of rows in the section.
return myAllowedList.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
//Configure the Cell
let CellID: NSString = "Allowed"
var cell: UITableViewCell = tableView.dequeueReusableCellWithIdentifier(CellID) as UITableViewCell
var data: NSManagedObject = myAllowedList[indexPath.row] as NSManagedObject
cell.textLabel.text = (data.valueForKeyPath("name")as String)
var pri = data.valueForKeyPath("price")as String
var str = data.valueForKeyPath("store")as String
cell.detailTextLabel?.text = "\(pri) name/s - \(str)"
return cell
}
//Override to support conditional editing of the table view
override func tableView(tableView: UITableView?, canEditRowAtIndexPath indexPath: NSIndexPath?) -> Bool {
//Return NO if you do not want the specified item to be editable
return true
}
//Override to support editing the table view
override func tableView(tableView: UITableView?, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath?) {
let appDel: AppDelegate = UIApplication.sharedApplication().delegate as AppDelegate
let context: NSManagedObjectContext = appDel.managedObjectContext!
if editingStyle == UITableViewCellEditingStyle.Delete {
if let tv = tableView {
context.deleteObject(myAllowedList[indexPath!.row] as NSManagedObject)
myAllowedList.removeAtIndex(indexPath!.row)
tv.deleteRowsAtIndexPaths([indexPath!.row], withRowAnimation: UITableViewRowAnimation.Fade)
}
var error: NSError? = nil
if !context.save(&error) {
abort()
}
}
}
}
My user editable text field code in the view controller are as follows.
{
class AllowedViewController: UIViewController {
#IBOutlet var textFieldname: UITextField!
#IBOutlet var textFieldstore: UITextField!
#IBOutlet var textFieldprice: UITextField!
var name: String = ""
var store: String = ""
var price: String = ""
var existingItem: NSManagedObject!
override func viewDidLoad() {
super.viewDidLoad()
if existingItem == nil {
textFieldname.text = name
textFieldstore.text = store
textFieldprice.text = price
}
// Do any additional setup after loading the view.
}
func saveTapped(sender: AnyObject) {
//Reference to our app delegate
let appDel: AppDelegate = UIApplication.sharedApplication().delegate as AppDelegate
//Reference NS Managed Object Context
let contxt: NSManagedObjectContext = appDel.managedObjectContext!
let en = NSEntityDescription.entityForName("FoodAllowed", inManagedObjectContext: contxt)!
//Check if item exists
if (existingItem != nil) {
existingItem.setValue(textFieldname.text as String, forKey: "name")
existingItem.setValue(textFieldstore.text as String, forKey: "store")
existingItem.setValue(textFieldprice.text as String, forKey: "price")
}else {
//Create instance of pur data model and intialize
var newItem = DataModel(entity: en, insertIntoManagedObjectContext: contxt)
//Map our properties
newItem.name = [textFieldname.text]
newItem.store = [textFieldstore.text]
newItem.price = [textFieldprice.text]
//Save our content
contxt.save(nil)
println(newItem)
//Navigate back to root view controll
self.navigationController?.popToRootViewControllerAnimated(true)
}
}
func cancelTapped(sender: AnyObject) {
//Navigate back to root view controll
self.navigationController?.popToRootViewControllerAnimated(true)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
}
My NSManaged DataModel is
{
#objc(DataModel)
class DataModel: NSManagedObject {
//properties feeding the attributes in our entity
//must match the entity attributes
#NSManaged var name: [String]
#NSManaged var store: [String]
#NSManaged var price: [String]
}
}
When I run the app in the simulator I get the following error
'NSInvalidArgumentException', reason: 'Unacceptable type of value for attribute: property = "name"; desired type = NSString; given type = Swift._NSSwiftArrayImpl; value = (Apples).'
What am I doing wrong?

Answer 1

The error message indicates that "name", "store" and "price" are String properties
of your Core Data entity, but you have defined them as [String], i.e. an array
of strings. It should be
#objc(DataModel)
class DataModel: NSManagedObject {
#NSManaged var name: String
#NSManaged var store: String
#NSManaged var price: String
}
And consequently
newItem.name = textFieldname.text // not: [textFieldname.text]
// ...
Better yet, let Xcode generate the managed object subclasses
(Editor -> Create NSManagedObject Subclass ... in the Xcode menu).