Question

我想要实现的是当用户创建，更改或删除persistent store上的数据时，它将与iCloud store同步，然后更新登录到同一iCloud帐户的其他设备。

我使用Objective-C资源创建了一个Core Data Stack，并试图在Swift中编写自己的资源但我在使用登录到同一个iCloud帐户的两个设备同步数据时遇到问题。

例如当 iDevice A 登录到iCloud时，它会将数据备份到iCloud，但当 iDevice B 登录到iCloud时，应用程序会删除持久存储上已有的任何数据以保存iCloud up，并且商店设备之间的任何更改都不会出现在另一个上，但似乎保存到iCloud商店作为最新备份，所以如果应用程序被删除并重新安装，我会看到其他设备所做的最新备份 - 这个请记住，如果 iDevice B 已经登录，则不会使用来自 iDevice A 的数据，除非重新安装该应用并且最后一次备份是由其他设备进行的。

有人知道我在Core data stack出错的地方使用相同的iCloud帐户同步两台设备之间的数据吗？

核心数据堆栈：

// MARK: - Core Data stack
// All the following code is in my appDelgate Core data stack 

func observeCloudActions(persistentStoreCoordinator psc:      NSPersistentStoreCoordinator?) {
// Register iCloud notifications observers for;

//Stores Will change 
//Stores Did Change 
//persistentStoreDidImportUbiquitousContentChanges
//mergeChanges

}

//Functions for notifications

func mergeChanges(notification: NSNotification) {
NSLog("mergeChanges notif:\(notification)")
if let moc = managedObjectContext {
    moc.performBlock {
        moc.mergeChangesFromContextDidSaveNotification(notification)
        self.postRefetchDatabaseNotification()
    }
 }
}

  func persistentStoreDidImportUbiquitousContentChanges(notification: NSNotification) {
self.mergeChanges(notification);
 }    

func storesWillChange(notification: NSNotification) {
NSLog("storesWillChange notif:\(notification)");
if let moc = self.managedObjectContext {
    moc.performBlockAndWait {
        var error: NSError? = nil;
        if moc.hasChanges && !moc.save(&error) {
            NSLog("Save error: \(error)");
        } else {
            // drop any managed objects
        }
        moc.reset();
    }

       NSNotificationCenter.defaultCenter().postNotificationName("storeWillChange", object: nil)

 }
}

 func storesDidChange(notification: NSNotification) {
NSLog("storesDidChange posting notif");
self.postRefetchDatabaseNotification();
//Sends notification to view controllers to reload data      NSNotificationCenter.defaultCenter().postNotificationName("storeDidChange", object: nil)

 }

func postRefetchDatabaseNotification() {
dispatch_async(dispatch_get_main_queue(), { () -> Void in
          NSNotificationCenter.defaultCenter().postNotificationName("storeDidChange", object: nil)

 })
 }


// 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 "hyouuu.pendo" in the application's documents Application Support directory.
let urls = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .UserDomainMask)
return urls[urls.count-1] as! NSURL
}()

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("AppName", withExtension: "momd")!
NSLog("modelURL:\(modelURL)")
return NSManagedObjectModel(contentsOfURL: modelURL)!
}()

lazy var persistentStoreCoordinator: NSPersistentStoreCoordinator? = {
// The persistent store coordinator for the application. This implementation creates and return 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
var coordinator: NSPersistentStoreCoordinator? = NSPersistentStoreCoordinator(managedObjectModel: self.managedObjectModel)


let documentsDirectory = NSFileManager.defaultManager().URLsForDirectory(NSSearchPathDirectory.DocumentDirectory, inDomains: NSSearchPathDomainMask.UserDomainMask).last as! NSURL


let storeURL = documentsDirectory.URLByAppendingPathComponent("CoreData.sqlite")

NSLog("storeURL:\(storeURL)")

let storeOptions = [NSPersistentStoreUbiquitousContentNameKey:"AppStore"]

var error: NSError? = nil
var failureReason = "There was an error creating or loading the application's saved data."

if coordinator!.addPersistentStoreWithType(
    NSSQLiteStoreType,
    configuration: nil,
    URL: storeURL,
    options: storeOptions,
    error: &error) == nil
{
    coordinator = nil
    // Report any error we got.
    let dict = NSMutableDictionary()
    dict[NSLocalizedDescriptionKey] = "Failed to initialize the application's saved data"
    dict[NSLocalizedFailureReasonErrorKey] = failureReason
    dict[NSUnderlyingErrorKey] = error
    error = NSError(domain: "Pendo_Error_Domain", code: 9999, userInfo: dict as [NSObject : AnyObject])
    // 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("AddPersistentStore error \(error), \(error!.userInfo)")
}

self.observeCloudActions(persistentStoreCoordinator: coordinator)

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
if coordinator == nil {
    return nil
}
var managedObjectContext = NSManagedObjectContext(concurrencyType: NSManagedObjectContextConcurrencyType.MainQueueConcurrencyType)
managedObjectContext.mergePolicy = NSMergeByPropertyObjectTrumpMergePolicy
managedObjectContext.persistentStoreCoordinator = coordinator
return managedObjectContext
}()

Answer 1

这是我如何进行我的设置，它同步我的核心数据，并保持同步变化。

这来自我的AppDelegate。

let one: Int = { return 1 }()

Answer 2

我认为对我和你的代码有用的区别是：

1）我不知道你在哪里添加了NSPersistentStoreDidImportUbiquitousContentChangesNotification的观察者，例如在代码中：

let nc : NSNotificationCenter = NSNotificationCenter.defaultCenter();
let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
nc.addObserver(self, selector: "dataUpdated:",
        name: NSPersistentStoreDidImportUbiquitousContentChangesNotification,
        object: self.managedObjectContext?.persistentStoreCoordinator)

2）在我捕获通知的函数的代码中（在本例中为dataUpdated），它在更新显示以显示新数据之前使用以下代码重置托管objext上下文：

let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
if let managedObjectContext = appDelegate.managedObjectContext {
     managedObjectContext.reset()
}

重置托管对象上下文后，我使用代码再次获取实体：

let fetchRequest = NSFetchRequest(entityName: "ClassNameHere")
let sortDescriptor = NSSortDescriptor(key: "name", ascending: true)
fetchRequest.sortDescriptors = [sortDescriptor]
let fetchResults = managedObjectContext!.executeFetchRequest(fetchRequest, error: nil) as! [ClassNameHere]

如何使用Core Data＆amp; amp; icloud的？

2 个答案: