使用iCloud启用的核心数据NSArray获取方法

Question

我一直在我的应用程序中设置和测试核心数据，本地一切都很好；然而，一旦我通过启用iCloud

NSDictionary *options;
    if ([self iCloudEnabled]) {
        options = @{NSSQLitePragmasOption: @{@"journal_mode" : @"DELETE"},
                    NSPersistentStoreUbiquitousContentNameKey : @"iCloudStore"};
        [self subscribeToNotifications];
    } else
        options = @{NSSQLitePragmasOption: @{@"journal_mode" : @"DELETE"}};

运行我的应用程序，我在控制台中收到以下错误：

*** ERROR: this process has called an NSArray-taking method, such as initWithArray:, and passed in an NSSet object.  This is being worked-around for now, but will soon cause you grief.

打印完成该错误后，一切似乎都正常工作。

我能找到的其他相关问题只有这里和这里，它们都没有帮助。

我甚至找不到任何地方能说明这个错误的含义。

感谢您的帮助。

编辑：据我所知，这是在我的managedObjectContext初始化之后，在"使用本地存储：0"打印到控制台之前发生的。问题是，我不知道当时正在执行什么（因为我没有调用任何东西）；它似乎在后台线程中。

第二版：我还应该提到，这只发生在应用程序第一次启动时（在iCloud"一次性"设置中）。

编辑3：这是初始化我的上下文的代码：

- (NSURL *)coreDataLocalURL {
    // The directory the application uses to store the Core Data store file.
    NSURL *result = [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
    result = [result URLByAppendingPathComponent:@"TheAnglersLog"];
    NSError *e;
    if (![[NSFileManager defaultManager] fileExistsAtPath:result.path])
        // create TheAnglersLog directory if it doesn't exist
        [[NSFileManager defaultManager] createDirectoryAtPath:result.path
                                  withIntermediateDirectories:NO
                                                   attributes:nil
                                                        error:&e];
    return result;
}
- (NSManagedObjectModel *)managedObjectModel {
    // The managed object model for the application. It is a fatal error for the application not to be able to find and load its model.
    if (_managedObjectModel != nil)
        return _managedObjectModel;
    NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"TheAnglersLog" withExtension:@"momd"];
    _managedObjectModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL];
    return _managedObjectModel;
}
- (NSPersistentStoreCoordinator *)persistentStoreCoordinator {
    // The persistent store coordinator for the application. This implementation creates and return a coordinator, having added the store for the application to it.
    if (_persistentStoreCoordinator != nil) {
        return _persistentStoreCoordinator;
    }
    // Create the coordinator and store
    _persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:[self managedObjectModel]];
    NSURL *storeURL = [[self coreDataLocalURL] URLByAppendingPathComponent:@"TheAnglersLog.sqlite"];
    NSError *error = nil;
    NSString *failureReason = @"There was an error creating or loading the application's saved data.";
    NSDictionary *options;
    if ([self iCloudEnabled]) {
        options = @{NSSQLitePragmasOption: @{@"journal_mode" : @"DELETE"},
                    NSPersistentStoreUbiquitousContentNameKey : @"TheAnglersLogCloudStore"};
        [self subscribeToNotifications];
    } else
        options = @{NSSQLitePragmasOption: @{@"journal_mode" : @"DELETE"}};
    NSLog(@"Is iCloud enabled? %@", [self iCloudEnabled] ? @"YES" : @"NO");
    NSPersistentStore *store;
    if (!(store = [_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeURL options:options error:&error])) {
        // Report any errors we got.
        NSMutableDictionary *dict = [NSMutableDictionary dictionary];
        dict[NSLocalizedDescriptionKey] = @"Failed to initialize the application's saved data";
        dict[NSLocalizedFailureReasonErrorKey] = failureReason;
        dict[NSUnderlyingErrorKey] = error;
        error = [NSError errorWithDomain:@"YOUR_ERROR_DOMAIN" code:9999 userInfo:dict];
        NSLog(@"Error in persistentStoreCoordinator: %@, %@", error, [error userInfo]);
    }
    NSLog(@"Core Data URL: %@", [store URL]);
    return _persistentStoreCoordinator;
}
- (NSManagedObjectContext *)managedObjectContext {
    // Returns the managed object context for the application (which is already bound to the persistent store coordinator for the application.)
    if (_managedObjectContext != nil) {
        return _managedObjectContext;
    }
    NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator];
    if (!coordinator) {
        return nil;
    }
    _managedObjectContext = [[NSManagedObjectContext alloc] init];
    [_managedObjectContext setPersistentStoreCoordinator:coordinator];
    return _managedObjectContext;
}

Answer 1

它准确地告诉了你问题所在：在某个地方（而不是你发布的代码中），你正在将NSSet传递给某个需要NSArray的东西。NSArray是有序且包含重复的，NSSet是无序且包含重复。它把它转换成了一套给你的，这样它就不会崩溃，但它抱怨说，它将来可能不会继续这样做了。