deleteRowsAtIndexPaths冻结UITableView

Question

我有一个UITableView核心数据。

当我插入新记录或更新现有记录时，一切进展顺利，UITableView会自动更新，但是当我删除记录时，UITableView冻结，直到UIView重新加载。

有人知道发生了什么问题吗？

- (void)controllerWillChangeContent:(NSFetchedResultsController *)controller 
{ 
    [self.tableView beginUpdates]; 
} 

- (void)controller:(NSFetchedResultsController *)controller didChangeSection:(id <NSFetchedResultsSectionInfo>)sectionInfo 
      atIndex:(NSUInteger)sectionIndex forChangeType:(NSFetchedResultsChangeType)type 
{ 
    switch(type) { 
     case NSFetchedResultsChangeInsert: 
      [self.tableView insertSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade]; 
      break; 

     case NSFetchedResultsChangeDelete: 
      [self.tableView deleteSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade]; 
      break; 
    } 
} 

- (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject 
     atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type 
     newIndexPath:(NSIndexPath *)newIndexPath 
{ 
    UITableView *tableView = self.tableView; 

    switch(type) { 
     case NSFetchedResultsChangeInsert: 
      [tableView insertRowsAtIndexPaths:@[newIndexPath] withRowAnimation:UITableViewRowAnimationFade]; 
      break; 

     case NSFetchedResultsChangeDelete: 
      [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade]; 
      break; 

     case NSFetchedResultsChangeUpdate: 
      [tableView reloadRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade]; 

      break; 

     case NSFetchedResultsChangeMove: 
      [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade]; 
      [tableView insertRowsAtIndexPaths:@[newIndexPath] withRowAnimation:UITableViewRowAnimationFade]; 
      break; 
    } 
} 

- (void)controllerDidChangeContent:(NSFetchedResultsController *)controller 
{ 
    [self.tableView endUpdates]; 
} 

，我删除记录并保存上下文

- (void)refreshData 
{ 
    dispatch_queue_t fetchQ = dispatch_queue_create("Data Fetch", NULL); 
    dispatch_async(fetchQ, ^{ 

     // here I delete some records    

     dispatch_async(dispatch_get_main_queue(), ^(void) { 
      [self saveContext]; 
     }); 
    }); 
} 
- (void)saveContext 
{ 
    NSError *error = nil; 
    NSManagedObjectContext *managedObjectContext = self.managedObjectContext; 
    if (managedObjectContext != nil) { 
     if ([managedObjectContext hasChanges] && ![managedObjectContext save:&error]) { 
      // Replace this implementation 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(@"Unresolved error %@, %@", error, [error userInfo]); 
      abort(); 
     } 
    } 
} 

Answer 1

当我删除调度队列一切工作正常的代码。