NSFetchedResultsController创建太多部分

我复制从苹果的代码文件的NSFetchedResultsController。它说，sectionNameKeyPath如果我想为显示结果的UITableView划分我的结果，则应提供。

我旨在根据模型对象名称开头的字符来区分结果。即按名称排序。

这段代码完全可以做到这一点（按名称排序），但是每一行都显示在自己的部分中，而不是对行组进行分区。（节数基本上等于行数）。

我相信我在某个地方犯了一个愚蠢的错误，但是现在我花了两个半小时，看不到任何东西。我只是要粘贴要在其中显示数据的UITableView的委托/数据源方法。

#pragma mark NSFetchedResultsController
- (NSFetchedResultsController *)fetchedResultsController {
    if (_fetchedResultsController != nil) {
        return _fetchedResultsController;
    }

    NSFetchRequest *fetchRequest = [Place MR_requestAllSortedBy:@"name" ascending:YES];
    [fetchRequest setFetchLimit:0];
    [fetchRequest setFetchBatchSize:20];

    NSFetchedResultsController *theFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:[NSManagedObjectContext MR_contextForCurrentThread] sectionNameKeyPath:@"name" cacheName:@"places"];
    _fetchedResultsController = theFetchedResultsController;
    _fetchedResultsController.delegate = self;
    return _fetchedResultsController;
}


#pragma mark UITableViewDelegate
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    ListTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:listTableViewCellIdentifier];

    Place *place = [_fetchedResultsController objectAtIndexPath:indexPath];

    FAKIcon *categoryIcon = [FFPlaceHandler getIconForPlaceWithCategoryID:place.main_category andSize:CELL_ICON_SIZE];
    [categoryIcon addAttribute:NSForegroundColorAttributeName value:FF_WHITE_COLOR];

    FAKIcon *circleIcon = [FAKFontAwesome circleIconWithSize:CELL_ICON_CIRCLE_SIZE];
    [circleIcon addAttribute:NSForegroundColorAttributeName value:[FFPlaceHandler getColorForPlaceWithCategoryID:place.main_category]];

    cell.image.image = [UIImage imageWithStackedIcons:@[circleIcon, categoryIcon] imageSize:CGSizeMake(CELL_ICON_CIRCLE_SIZE, CELL_ICON_CIRCLE_SIZE)];

    cell.title.text = place.name;
    cell.addressLabel.text = place.place_contact_info.address;

    [cell setDistanceWithDistance:[place.distance_from_user floatValue]];

    cell.indexPath = indexPath;
    cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;

    return cell;
}

#pragma mark UITableViewDatasource

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {
    if ([[_fetchedResultsController sections] count] > 1) {
        id <NSFetchedResultsSectionInfo> sectionInfo = [[_fetchedResultsController sections] objectAtIndex:section];
        return [sectionInfo name];
    } else
        return nil;
}

- (NSArray *)sectionIndexTitlesForTableView:(UITableView *)tableView {
    return [_fetchedResultsController sectionIndexTitles];
}

- (NSInteger)tableView:(UITableView *)tableView sectionForSectionIndexTitle:(NSString *)title atIndex:(NSInteger)index {
    return [_fetchedResultsController sectionForSectionIndexTitle:title atIndex:index];
}


- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section
{
    return 40.0;
}

- (NSInteger)tableView:(UITableView *)table numberOfRowsInSection:(NSInteger)section {
    if ([[_fetchedResultsController sections] count] > 1) {
        id <NSFetchedResultsSectionInfo> sectionInfo = [[_fetchedResultsController sections] objectAtIndex:section];
        return [sectionInfo numberOfObjects] ;
    } else
        return 0;
}

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return [[_fetchedResultsController sections] count];
}

为什么UITableViewCell分配给的每个部分都没有按字母顺序排列？

编辑：

通过在核心数据中的放置表中添加字段来解决该问题。该字段保存每个记录的第一个字符。在此之后，我更改了sectionKeyPath在此方法中看到的内容：

#pragma mark NSFetchedResultsController
- (NSFetchedResultsController *)fetchedResultsController {
    if (_fetchedResultsController != nil) {
        return _fetchedResultsController;
    }

    NSFetchRequest *fetchRequest = [Place MR_requestAllSortedBy:@"name" ascending:YES];
    [fetchRequest setFetchLimit:0];
    [fetchRequest setFetchBatchSize:20];

    NSFetchedResultsController *theFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:[NSManagedObjectContext MR_contextForCurrentThread] sectionNameKeyPath:@"name_first_character" cacheName:@"places"];
    _fetchedResultsController = theFetchedResultsController;
    _fetchedResultsController.delegate = self;
    return _fetchedResultsController;
}

此外i取代了> 1与> 0所建议MOBY！我现在有一些不错的部分：）