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iOS

Posted by Rohit Das
Rohit Das
4,356 Points

CoreData and Swift - User Login

Hi there,

So I am creating an iOS application and want to allow users to log in and out/register. I am doing this using core Data and currently my program allows users to register, but the data isn't saved so when they try and log in, it says incorrect username/password, in other words, the program isn't recognizing the fact that the user already input their information when creating/registering their account and as a result cannot load the information they input and won't allow the user to log in. This is the code I have for when a user clicks the register button. Please help:

import UIKit
import CoreData

class RegisterPageViewController: UIViewController {
    @IBOutlet weak var userEmailTextField: UITextField!
    @IBOutlet weak var userPasswordTextField: UITextField!
    @IBOutlet weak var confirmPasswordTextField: UITextField!

    override func viewDidLoad() {
        super.viewDidLoad()
    }

    @IBAction func registerButtonTapped(sender: AnyObject) {

        let userEmail = userEmailTextField.text
        let userPassword = userPasswordTextField.text
        let userConfirmPassword = confirmPasswordTextField.text

        if (userEmail.isEmpty || userPassword.isEmpty || userConfirmPassword.isEmpty) {

            displayMyAlertMessage("You haven't filled out all the fields.")
            return;  
        }

        if (userPassword != userConfirmPassword) {

            displayMyAlertMessage("Passwords do not match.")
            return;

        }

        var appDel: AppDelegate = (UIApplication.sharedApplication().delegate as AppDelegate)
        var context:NSManagedObjectContext = appDel.managedObjectContext!
        var newUser = NSEntityDescription.insertNewObjectForEntityForName("Users", inManagedObjectContext: context) as NSManagedObject

        context.save(nil)

        var successAlert = UIAlertController(title: "Alert", message: "Successfully registered.", preferredStyle: UIAlertControllerStyle.Alert)
        let okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.Default) { action in
            self.dismissViewControllerAnimated(true, completion: nil)
        }
        successAlert.addAction(okAction)
        self.presentViewController(successAlert, animated: true, completion: nil)
    }

What do you think is going wrong? Pasan Premaratne Amit Bijlani

I would really appreciate if I got some help for this! Thanks!

1 Answer

Stephen Whitfield
Stephen Whitfield
16,771 Points

^They're probably saved in your .xcdatamodeld but not in your subclassed NSManagedObject files. You need to update those files with the newly added attributes.

Rohit Das
Rohit Das
4,356 Points

Thank you for the response! I have not created an NSManagedObject file, what do you suggest I do?

Stephen Whitfield
Stephen Whitfield
16,771 Points

Ah! You probably should as it's a great way to keep track of your models. Click on the Entity in the xcdatamodeld, click on Editor in the toolbar, click "Create NSManagedObject Subclass", click next, make sure you select the entity you're wanting to subclass, and you should be good to go.

Rohit Das
Rohit Das
4,356 Points

Ok great! I've created my NSManagedObject file and this is what that file says as of right now:

import Foundation import CoreData

class Users: NSManagedObject {

@NSManaged var password: String
@NSManaged var username: String

}

The same error persists. Also, I was not using CoreData earlier and just recently decided to use CoreData for my app, so my login file looks like this:

@IBAction func loginButtonTapped(sender: AnyObject) {

    let userEmail = userEmailTextField.text
    let userPassword = userPasswordTextField.text

    let userEmailStored = NSUserDefaults.standardUserDefaults().stringForKey("userEmail")
    let userPasswordStored = NSUserDefaults.standardUserDefaults().stringForKey("userPassword")

    if (userEmailStored == userEmail && userPasswordStored == userPassword) {
        NSUserDefaults.standardUserDefaults().setBool(true, forKey: "isUserLoggedIn")
        NSUserDefaults.standardUserDefaults().synchronize()
        self.dismissViewControllerAnimated(true, completion: nil)
    }

    else {
        var failAlert = UIAlertController(title: "Alert", message: "Your username or password is incorrect.", preferredStyle: UIAlertControllerStyle.Alert)
        let okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.Default, handler: nil)
        failAlert.addAction(okAction)
        self.presentViewController(failAlert, animated: true, completion: nil)

    }

Do you know of what I should change so that it accesses the new objects I'm saving using CoreData? I apologize, but it is rather difficult to find information on Swift as it is a relatively new language.

Thank you very much again.