CODEWITHSUNDEEP
iosswiftcore-dataswift2
O user
O user

Reputation: 97

How to store one value using core-data ? (swift 2)

I'm developing an app to store one phone number at time using core data, the user should be able to enter a new phone number into ui text field,if it's equal to nil, it should store a new phone number,else it should replace old number with new number; it should store only one value.

but the code doesn't work as it should

what's wrong in my code?

  let moContext: AppDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
            let context: NSManagedObjectContext = moContext.managedObjectContext
            let phoneNu = NSEntityDescription.insertNewObjectForEntityForName("Setting", inManagedObjectContext: context)


            let fetchRequest = NSFetchRequest(entityName: "Setting")
            fetchRequest.predicate = NSPredicate(format: "phoneNumber = %@", phoneNumber)
           // phoneNu.setValue(phoneNumber.text, forKey: "phoneNumber")



            do{
                let request = NSFetchRequest(entityName: "Setting")
                let phoneN = try context.executeFetchRequest(request)
                if phoneN.count == 0{
                    phoneNu.setValue(phoneNumber.text, forKey: "phoneNumber")
                }else if phoneN.count != 0{
                  for item in phoneN as! [NSManagedObject]{

                    let number = item.valueForKey("phoneNumber")
                    number?[0]?.setValue(phoneNumber.text, forKey: "phoneNumber")
                    }
                }
            }catch{

                print("error")

            }


            do{

                let request = NSFetchRequest(entityName: "Setting")
                let phoneNumber = try context.executeFetchRequest(request)

                if phoneNumber.count > 0{
                    for item in phoneNumber as! [NSManagedObject]{

                        let number = item.valueForKey("phoneNumber")

                        print(number!)
                    }
                }


            }catch{

            }

Upvotes: 0

Views: 636

Answers (2)

dmlebron
dmlebron

Reputation: 861

This is my solution

let moContext: AppDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
let context: NSManagedObjectContext = moContext.managedObjectContext

guard let phoneNumber = phoneNumber.text where phoneNumber.characters.count > 0 else {
    return// returns if textField is empty.
}

let fetchRequest = NSFetchRequest(entityName: "Setting")
fetchRequest.predicate = NSPredicate(format: "phoneNumber = %@", phoneNumber)

do{
   let request = NSFetchRequest(entityName: "Setting")
   let phoneObjectArray = try context.executeFetchRequest(request)

   guard let settingFetched = phoneObjectArray as? [Setting] where settingFetched.count > 0 else {
    // if enters here -> 0 phone numbers were found

       if let setting = NSEntityDescription.insertNewObjectForEntityForName("Setting", inManagedObjectContext: context) as? Setting {
        setting.phoneNumber = phoneNumber

        // call context.save()
       }

    return // this I forgot
   }

let settingObject = settingFetched.first

// fetch results return store phone number.
// update phone number
settingObject.phoneNumber = phoneNumber
// call context.save()

} catch let error as NSError! {
  print("error: \(error)")

}

You need to call the "save()" function to persist the information.

I did some changes to the name variables, added some validations and assume some model class name based on your code. I always recommend to use your NSManagedObject subclass (Setting I assume) instead of just using NSManagedObject and key/value coding.

There could be some minor syntax mistakes on the code because I was using a text editor.

Hope this helps!

Upvotes: 1

Mundi
Mundi

Reputation: 80273

For what you want to do, Core Data is overkill.

Use NSUserDefaults instead. So much easier.

Upvotes: 1

Related Questions