OSX和iOS之间的iCloud Core数据共享

Question

我有一个OSX和iOS的应用程序,都使用iCloud在它们之间共享核心数据.当我在iPhone上进行更改时,我可以在OSX应用程序中看到它们,并NSPersistentStoreDidImportUbiquitousContentChangesNotification在两个应用程序中调用它们,因此iOS - > Mac运行良好.但是当我在Mac应用程序中进行一些更改时,我无法在iPhone中看到它们.iPhone永远不会打电话给NSPersistentStoreDidImportUbiquitousContentChangesNotification.我能改变Mac的唯一方法是在iPhone上做一些改变.然后我可以看到所有的变化.

两个项目中的iCloud集成是一样的.核心数据数据模型是相同的.权利也是一样的.

我的所有代码都基于这个库:http://ossh.com.au/design-and-technology/software-development/sample-library-style-ios-core-data-app-with-icloud-integration/

为什么iPhone在iPhone上进行一些更改之前没有改变Mac？有任何想法吗？

另一个问题

在我的应用程序中,当用户启用iCloud时,我检查是否已经是iCloud上的文件.如果文件存在,则用户可以选择从iCloud文件还原核心数据或从本地存储启动新副本.要开始新副本,我使用以下代码:

- (void)startNewCopy
{
    [self removeICloudStore];
    [self moveStoreToIcloud];
}

- (void)removeICloudStore
{
    BOOL result;
    NSError *error;
    // Now delete the iCloud content and file
    result = [NSPersistentStoreCoordinator removeUbiquitousContentAndPersistentStoreAtURL:[self icloudStoreURL]
                                                                             options:[self icloudStoreOptions]
                                                                             error:&error];
    if (!result)
    {
        NSLog(@"Error removing store");
    }
    else
    {
        NSLog(@"Core Data store removed.");
        // Now delete the local file
        [self deleteLocalCopyOfiCloudStore];
    }

}


- (void)deleteLocalCopyOfiCloudStore {
   // We need to get the URL to the store
   NSError *error = nil;
   [[NSFileManager defaultManager] removeItemAtURL:[self localUbiquitySupportURL] error:&error];
}

- (void)moveStoreToIcloud
{
     // Open the store
     NSPersistentStore *sourceStore = [[_persistentStoreCoordinator persistentStores] firstObject];

     if (!sourceStore)
     {
         NSLog(@" failed to add old store");
     }
     else
     {
         NSLog(@" Successfully added store to migrate");
         NSError *error;
         id migrationSuccess = [_persistentStoreCoordinator migratePersistentStore:sourceStore toURL:[self icloudStoreURL] options:[self icloudStoreOptions] withType:NSSQLiteStoreType error:&error];

         if (migrationSuccess)
         {
             NSLog(@"Store migrated to iCloud");

             _persistentStoreCoordinator = nil;
             _managedObjectContext = nil;

             // Now delete the local file
             [self deleteLocalStore];

         }
         else
         {
             NSLog(@"Failed to migrate store: %@, %@", error, error.userInfo);

         }
     }

}

- (void)deleteLocalStore
{
     NSError *error = nil;
     [[NSFileManager defaultManager] removeItemAtURL:[self localStoreURL] error:&error];
}

从单个设备执行此操作似乎都运行良好,但是当我尝试使用多个设备时,我遇到了一些错误.

例:

我有两个设备.第一个没有连接到iCloud,第二个连接到iCloud.在我启用iCloud的第一个设备中,我选择startNewCopy然后在第二个设备中我收到此错误:

CoreData:Ubiquity:Librarian在开始下载时返回严重错误Error Domain = BRCloudDocsErrorDomain Code = 5"操作无法完成.(BRCloudDocsErrorDomain错误5 - URL上没有文档)"

该NSPersistentStoreCoordinatorStoresDidChangeNotification错误之前不会被调用.

这是我的通知代码:

- (void)processStoresDidChange:(NSNotification *)notification
{
      NSLog(@"processStoresDidChange");
      // Post notification to trigger UI updates

      // Check type of transition
      NSNumber *type = [notification.userInfo objectForKey:NSPersistentStoreUbiquitousTransitionTypeKey];

      //NSLog(@" userInfo is %@", notification.userInfo);
      //NSLog(@" transition type is %@", type);

      if (type.intValue == NSPersistentStoreUbiquitousTransitionTypeInitialImportCompleted) {

          NSLog(@" transition type is NSPersistentStoreUbiquitousTransitionTypeInitialImportCompleted");

      } else if (type.intValue == NSPersistentStoreUbiquitousTransitionTypeAccountAdded) {
          NSLog(@" transition type is NSPersistentStoreUbiquitousTransitionTypeAccountAdded");
      } else if (type.intValue == NSPersistentStoreUbiquitousTransitionTypeAccountRemoved) {
          NSLog(@" transition type is NSPersistentStoreUbiquitousTransitionTypeAccountRemoved");
      } else if (type.intValue == NSPersistentStoreUbiquitousTransitionTypeContentRemoved) {
          NSLog(@" transition type is NSPersistentStoreUbiquitousTransitionTypeContentRemoved");
      }

      [[NSOperationQueue mainQueue] addOperationWithBlock:^ {

          if (type.intValue == NSPersistentStoreUbiquitousTransitionTypeContentRemoved) {

              [self deleteLocalStore];
              _persistentStoreCoordinator = nil;
              _managedObjectContext = nil;

              NSLog(@" iCloud store was removed! Wait for empty store");
          }

          // Refresh user Interface
          [[NSNotificationCenter defaultCenter] postNotificationName:@"notiIcloud" object:@"storeChanged"];
      }];

}

如何检测iCloud内容已被删除并避免上述错误？

Answer 1

在我看来，您可能没有使用适当的接口。

您无需使用任何方法即可将文件移入或移出 iCloud NSPersistentStore。通常，适当的操作也必须包含在调用中NSFileCoordinator。

这是我在 iOS 上所做的。toLocal表示移动到本地（设备）存储或从本地（设备）存储移动：

//
/// Move file between stores (assumed no name clash).
/// Return new URL.
/// Note: cloud file moves are asynchronous.
///
- (NSURL *)moveStoreFile:(NSURL *)url toRootURL:(NSURL *)rootURL toLocal:(BOOL)toLocal
{
    NSURL *newURL = rootURL;
    if (!toLocal)
        newURL = [newURL URLByAppendingPathComponent:@"Documents"];
    newURL = [newURL URLByAppendingPathComponent:url.lastPathComponent];

    [self backupFile:url isLocal:!toLocal completionHandler:
     ^(BOOL success) {

        MRLOG(@"MOVE %s %@ to %s %@", toLocal? "icloud" : "local", [url lastPathComponent],
              toLocal? "local" : "icloud", [newURL lastPathComponent]);

        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0),
        ^{
           NSError *error;
           // setUbiquitous does file coordination
           BOOL msuccess = [[NSFileManager defaultManager]
                           setUbiquitous:!toLocal itemAtURL:url destinationURL:newURL error:&error];

           dispatch_async(dispatch_get_main_queue(),
           ^{
              if (!msuccess)
                  MRLOG(@"move failed: %@", error);
              [self.delegate moveStoreFileCompletedWithStatus:success error:error];
           });
        });
    }];

    return newURL;
}

删除需要明确的文件协调：

///
/// Purge backup file (really delete it).
/// Note: cloud deletes are asynchronous.
///
- (void)purgeFile:(NSURL *)url isLocal:(BOOL)isLocal
{
    MRLOG(@"PURGE %s %@", isLocal? "local" : "icloud", [url lastPathComponent]);

    if (isLocal)
        [self removeFile:url];
    else
        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0),
        ^{
            NSError *coordinationError;
            NSFileCoordinator *coordinator = [[NSFileCoordinator alloc] initWithFilePresenter:nil];

            [coordinator coordinateWritingItemAtURL:url options:NSFileCoordinatorWritingForDeleting
                                                    error:&coordinationError
                                     byAccessor:
             ^(NSURL* writingURL)
             {
                 [self removeFile:writingURL];
             }];
            if (coordinationError) {
                MRLOG(@"coordination error: %@", coordinationError);
                [(SSApplication *)[SSApplication sharedApplication] fileErrorAlert:coordinationError];
            }
        });
}

要检测文件的更改，您需要使用NSMetadataQuery并添加观察者NSMetadataQueryDidUpdateNotification。