ipad – Coredata将sqlite保存到Dropbox – 还原问题 – 在应用重新启动之前不会重新加载Sqlite文件

我有一个使用Core Data的iPad应用程序.

我正在尝试使用sqlite文件的Dropbox同步来为我的用户提供另一种备份方式.

从Dropbox备份和恢复是没有问题的;但是,一旦恢复,必须重置应用程序以显示数据.

我假设这是因为持久存储仍在使用旧文件.

如何强制关闭旧模型并重新打开?

我试过以下没有运气:

 NSPersistentStore* store = [[_persistentStoreCoordinator persistentStores] lastObject];
[_persistentStoreCoordinator removePersistentStore:store error:nil];
[__managedObjectModel release];
__managedObjectModel = nil;
[_persistentStoreCoordinator release];
_persistentStoreCoordinator = nil;
[self persistentStoreCoordinator];
[self managedObjectContext];
[self managedObjectModel];

最佳答案 最后,我使用以下内容,重新加载持久存储:

NSError *error;
// retrieve the store URL
NSURL * storeURL = [[__managedObjectContext persistentStoreCoordinator] URLForPersistentStore:[[[__managedObjectContext persistentStoreCoordinator] persistentStores] lastObject]];
// lock the current context
[__managedObjectContext lock];
[__managedObjectContext reset];//to drop pending changes
//delete the store from the current managedObjectContext
if ([[__managedObjectContext persistentStoreCoordinator] removePersistentStore:[[[__managedObjectContext persistentStoreCoordinator] persistentStores] lastObject] error:&error])
{

    NSDictionary *options = [NSDictionary dictionaryWithObjectsAndKeys:
                             [NSNumber numberWithBool:YES], NSMigratePersistentStoresAutomaticallyOption,
                             [NSNumber numberWithBool:YES], NSInferMappingModelAutomaticallyOption, nil];
    [[__managedObjectContext persistentStoreCoordinator] addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeURL options:options error:&error];//recreates the persistent store
}

dispatch_async(dispatch_get_main_queue(), ^{
    self.ready = YES;
    [[NSNotificationCenter defaultCenter]postNotificationName:kModelDidChange object:nil];
});

[__managedObjectContext unlock];
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