如何使deleteRowsAtIndexPaths：使用GenericTableViewController？

I'm using Matt Gallagher's GenericTableViewController idea for controlling my UITableViews. My datasource is a NSFetchedResultsController.

我正在使用Matt Gallagher的GenericTableViewController理念来控制我的UITableViews。我的数据源是NSFetchedResultsController。

http://cocoawithlove.com/2008/12/heterogeneous-cells-in.html

Everything is working fine, until I try to delete a cell.

一切都运行正常，直到我尝试删除一个单元格。

I have the following code in my View Controller:

我在View Controller中有以下代码：

- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {

  if (editingStyle == UITableViewCellEditingStyleDelete) {

        // Delete the managed object.
        NSManagedObjectContext *context = [wineryController managedObjectContext];
        [context deleteObject:[wineryController objectAtIndexPath:indexPath]];

        NSError *error;
        if (![context save:&error]) {
            // Handle the error.
        }
        [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
  }   
}

The final line crashes with the rather verbose explanation in the console:

最后一行因控制台中相当冗长的解释而崩溃：

*** Terminating app due to uncaught exception 'NSInternalInconsistencyException',  
reason: 'Invalid update: invalid number of rows in section 0.  The number of rows   
contained in an existing section after the update (5) must be equal to the number  
of rows contained in that section before the update (5), plus or minus the number  
of rows inserted or deleted from that section (0 inserted, 1 deleted).'

OK, I understand what it is saying... a row is not getting deleted (I would assume) because I'm not forwarding some message to the right place (since I have moved some code from its 'normal' location)... anyone have any idea which one? I am totally stumped on this one.

好的，我理解它是什么意思......一行没有被删除（我会假设），因为我没有将一些消息转发到正确的地方（因为我已经从其'普通'位置移动了一些代码）。任何人都知道哪一个？我完全被这个问题困扰了。

1 个解决方案

#1

Well, bah. I just found this answer, which is not the same, but got me headed in the right direction. I'll leave this here for anyone in the future having similar troubles.

好吧，呸。我刚刚找到了这个答案，这不一样，但让我朝着正确的方向前进。我会留在这里为将来遇到类似麻烦的人。

The key is to wrap the deleteRowsAtIndexPaths with begin and end tags, and force the model to update within the same block, resulting in:

关键是用开始和结束标记包装deleteRowsAtIndexPaths，并强制模型在同一个块内更新，从而导致：

[tableView beginUpdates];
[self constructTableGroups];
[tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath]
        withRowAnimation:UITableViewRowAnimationFade];
[tableView endUpdates];

This caused the issue to go away, and the animations to work just perfectly.

这导致问题消失，动画完美地运作。

#1