Enabling Core Data Xcode Swift

Question

I am trying to enable core data in my project. Since I am already a fair way through my project, I have missed the option to enable core data at the start. can any one help me enable it? thank you

Answer 1

You can Directly add core data in your running project go to your project name right click on select new file and select Data Model form the coredata section and you have to some core data configuration in your AppDelegate.swift file....

add this code in AppDelegate file.....

import CoreData

// MARK: - Core Data stack

    lazy var applicationDocumentsDirectory: URL = {
        // The directory the application uses to store the Core Data store file. This code uses a directory named "com.purpleapps.PixBoxNew.PixBox" in the application's documents Application Support directory.
        let urls = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
        return urls[urls.count-1]
    }()

    lazy var managedObjectModel: NSManagedObjectModel = {
        // The managed object model for the application. This property is not optional. It is a fatal error for the application not to be able to find and load its model.
        let modelURL = Bundle.main.url(forResource: "<<YourCoredatanamehere>>", withExtension: "momd")!
        return NSManagedObjectModel(contentsOf: modelURL)!
    }()

    lazy var persistentStoreCoordinator: NSPersistentStoreCoordinator = {
        // The persistent store coordinator for the application. This implementation creates and returns a coordinator, having added the store for the application to it. This property is optional since there are legitimate error conditions that could cause the creation of the store to fail.
        // Create the coordinator and store
        let coordinator = NSPersistentStoreCoordinator(managedObjectModel: self.managedObjectModel)
        let url = self.applicationDocumentsDirectory.appendingPathComponent("SingleViewCoreData.sqlite")
        print(url)
        var failureReason = "There was an error creating or loading the application's saved data."
        do {
            let myOptions = [NSMigratePersistentStoresAutomaticallyOption: true,
                             NSInferMappingModelAutomaticallyOption: true]
            try coordinator.addPersistentStore(ofType: NSSQLiteStoreType, configurationName: nil, at: url, options: myOptions)
        } catch {
            // Report any error we got.
            var dict = [String: AnyObject]()
            dict[NSLocalizedDescriptionKey] = "Failed to initialize the application's saved data" as AnyObject?
            dict[NSLocalizedFailureReasonErrorKey] = failureReason as AnyObject?

            dict[NSUnderlyingErrorKey] = error as NSError
            let wrappedError = NSError(domain: "YOUR_ERROR_DOMAIN", code: 9999, userInfo: dict)
            // Replace this with code to handle the error appropriately.
            // abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
            NSLog("Unresolved error \(wrappedError), \(wrappedError.userInfo)")
            abort()
        }

        return coordinator
    }()

    lazy var managedObjectContext: NSManagedObjectContext = {
        // Returns the managed object context for the application (which is already bound to the persistent store coordinator for the application.) This property is optional since there are legitimate error conditions that could cause the creation of the context to fail.
        let coordinator = self.persistentStoreCoordinator
        //UNDO
        //         var managedObjectContext = NSManagedObjectContext(concurrencyType: .privateQueueConcurrencyType)
        var managedObjectContext = NSManagedObjectContext(concurrencyType: .mainQueueConcurrencyType)
        managedObjectContext.persistentStoreCoordinator = coordinator
        return managedObjectContext
    }()

    lazy var writerManagedObjectContext: NSManagedObjectContext = {
        // Returns the managed object context for the application (which is already bound to the persistent store coordinator for the application.) This property is optional since there are legitimate error conditions that could cause the creation of the context to fail.
        // let coordinator = self.persistentStoreCoordinator
        var writerManagedObjectContext = NSManagedObjectContext(concurrencyType: .privateQueueConcurrencyType)
        // writerManagedObjectContext.persistentStoreCoordinator = coordinator

        //   [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(_mocDidSaveNotification:) name:NSManagedObjectContextDidSaveNotification object:nil];

        NotificationCenter.default.addObserver(self, selector: #selector(AppDelegate.mocDidChangeNotification), name: NSNotification.Name.NSManagedObjectContextDidSave, object: nil)
        return writerManagedObjectContext
    }()
    // MARK: - Core Data Saving support

    func mocDidChangeNotification(_ notification : Notification){
        DispatchQueue.main.async {
            self.managedObjectContext.mergeChanges(fromContextDidSave: notification)
        }
    }

    func saveContext () {
        if managedObjectContext.hasChanges {
            do {
                try managedObjectContext.save()
            } catch {
                // Replace this implementation with code to handle the error appropriately.
                // abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
                let nserror = error as NSError
                NSLog("Unresolved error \(nserror), \(nserror.userInfo)")
                abort()
            }
        }
    }

Answer 2

Click on your app target (on the left pane its the top icon with the name of your app) then go to the 'Build Phases' tab then on 'Link Binary With Libraries', click the little '+' at the bottom then find 'CoreData.framework' and add it to your project

Start another new project with the core data option enabled. Copy those methods into your current project. You can do this one-by-one manually according to the methods that you require and would be used in your project. Also, don't forget to add:

import CoreData