Swift 3 Core Data Problem - Alle Daten fehlen

Question

Ich habe mein Core Data Projekt von Swift 2 auf Swift 3 aktualisiert. Ersetzen Sie den Core Data Stack durch NSPersistentContainer. Die neue Version kann jedoch keine alten Daten finden.

nach neuen Version installiert:

Swift 3 Version App keine Daten finden

Funktion Meine App ist Worte/Sätze zu erfassen und ihre Chinesische Bedeutung. Wenn ich diese Version im App Store veröffentliche, verlieren Benutzer alle ihre Datensätze nach der Aktualisierung.

Wie kann ich dieses Problem lösen?

Hier ist mein Swift 3-Code:

// 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 "social.street.NewWords" in the application's documents Application Support directory. 
    let urls = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask) 
    return urls[urls.count-1] 
}() 

lazy var persistentContainer: NSPersistentContainer = { 
    let modelURL = Bundle.main.url(forResource: "NewWords", withExtension: "momd")! 
    let container = NSPersistentContainer(name: "NewWords", managedObjectModel: NSManagedObjectModel(contentsOf: modelURL)!) 

    let documentsDirectory = FileManager.default.urls(for: FileManager.SearchPathDirectory.documentDirectory, in: FileManager.SearchPathDomainMask.userDomainMask) 

    let storeUrl = self.applicationDocumentsDirectory.appendingPathComponent("SingleViewCoreData.sqlite") 

    print(storeUrl) 

    container.persistentStoreDescriptions = [NSPersistentStoreDescription(url: storeUrl)] 

    container.loadPersistentStores(completionHandler: { (storeDescription, error) in 
     if let error = error as? NSError { 
      fatalError("Unresolved error \(error), \(error.userInfo)") 
     } 
    }) 
    return container 
}() 

Swift 2 Code:

// MARK: - Core Data stack 

lazy var applicationDocumentsDirectory: NSURL = { 
    // The directory the application uses to store the Core Data store file. This code uses a directory named "social.street.NewWords" in the application's documents Application Support directory. 
    let urls = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .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 = NSBundle.mainBundle().URLForResource("NewWords", withExtension: "momd")! 
    return NSManagedObjectModel(contentsOfURL: 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.URLByAppendingPathComponent("SingleViewCoreData.sqlite") 
    var failureReason = "There was an error creating or loading the application's saved data." 
    do { 
     try coordinator.addPersistentStoreWithType(NSSQLiteStoreType, configuration: nil, URL: url, options: nil) 
    } catch { 
     // Report any error we got. 
     var dict = [String: AnyObject]() 
     dict[NSLocalizedDescriptionKey] = "Failed to initialize the application's saved data" 
     dict[NSLocalizedFailureReasonErrorKey] = failureReason 

     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 
    var managedObjectContext = NSManagedObjectContext(concurrencyType: .MainQueueConcurrencyType) 
    managedObjectContext.persistentStoreCoordinator = coordinator 
    return managedObjectContext 
}() 

Wie Daten nach Code Swift 3 aufgerüstet bleiben?

zusätzlich: Swift 2-Version wird aus dem App Store installiert, und Swift 3-Version wird aus dem Xcode installiert.

Project's Github repo

Answer 1

Haben Sie geringes Gewicht mirgration umgesetzt?

, wenn Sie Ihre persistenten Speicher initialisieren können Sie ‚Optionen‘, für leichte Migration fügen hinzu:

let options = [NSMigratePersistentStoresAutomaticallyOption: true, 
        NSInferMappingModelAutomaticallyOption: true] 

Dann, wenn Sie die DB auf jeder App-Version ändern zuerst Sie zum .xcdatamodel gehen und gehen zu:

'editor' > 'Add Model Version' 

im oberen Menü, dann auf diese Version machen, um die Änderungen und stellen Sie sicher, dass es das grüne Häkchen auf hat, wenn Sie das Modell öffnen.