自定义UISearchDisplayController中搜索到结果的cell的位置

#pragma mark - UISearchBarDelegate
//当搜索文本被改变的时候调用
- (void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
{
　　//改变searchController中tableView的位置
    _searchController.searchResultsTableView.frame = CGRectMake(kZero, _tableViewY, kScreenW, kScreenH - _tableViewY);
    
    [[RealtimeSearchUtil currentUtil] realtimeSearchWithSource:self.dataSource searchText:(NSString *)searchText collationStringSelector:@selector(chatter) resultBlock:^(NSArray *results) {
        if (results) {
            dispatch_async(dispatch_get_main_queue(), ^{
                [self.searchController.resultsSource removeAllObjects];
                [self.searchController.resultsSource addObjectsFromArray:results];
                [self.searchController.searchResultsTableView reloadData];
            });
        }
    }];
}