controllerDidChangeContent：每次在核心数据中创建 ManagedObject 时调用
我有一个使用 NSFetchedResultsController 从核心数据存储加载数据的表视图，我正在实现controllerDidChangeContent：用新数据（从远程源加载）更新表，但是，一旦我创建，就会调用委托方法controllerDidChangeContent：一个托管对象，据我所知，只有当我在相应的托管对象上下文上发送消息 save: 时才应该调用它。
是否需要设置一个参数来启用此功能？
我正在下载一个 XML，其中包含许多要插入到表视图中的项目，但我遇到了崩溃，因为我正在动态创建托管对象并动态附加信息，其中一些信息需要显示在表视图单元格中。
因此，通过每次创建新的托管对象时调用controllerDidChangeContent：，我创建表视图单元格所需的属性尚未准备好。
任何见解都会很棒。
谢谢。
I have a tableview using NSFetchedResultsController to load data from the Core Data store, I am implementing controllerDidChangeContent: to update the table with new data (loaded from a remote source), however, the delegate method controllerDidChangeContent: is being called as soon as I create a Managed Object, it was my understanding that this should only be called when I message save: on the corresponding Managed Object Context.
Is there a parameter to set to enable this ?
I am downloading an XML with many items to insert into the tableview and I'm getting crashes because I am creating my Managed Objects on the fly and appending information on the fly, some of which are required to be displayed in the Table View Cell.
Therefore by controllerDidChangeContent: being called each time I create a new Managed Object, the properties I require to make the Table View Cell are not yet ready.
Any insight would be great.
Thanks.
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您无法禁用 NSFetchedResultsController 的此行为。为了防止这种情况，您可以创建第二个 NSManagedObjectContext，在那里执行所有插入、更改和删除操作，最后使用
mergeChangesFromContextDidSaveNotification：合并两个上下文：当您下载 XML 文件时，您也应该在后台执行此操作线程以防止 UI 因用户输入而被阻止。
You can't disable this behavior of the NSFetchedResultsController. To prevent this you can create a second NSManagedObjectContext, do all your inserts, changes and deletes there and finally merge both contexts with the
mergeChangesFromContextDidSaveNotification:As your are downloading an XML file you also should do this in a background thread to prevent the UI being blocked for user inputs.