NSFetchedResultContoller可以做到这一点吗？

Question

需要一些建议到：NSFetchedResultController可以做到这一点？

UITableView: 
    [section name] <= {entity: Section, value: title} 
    [cell title] <= {entity: Cell, value: title} 

Model: 
    [entity: Section, properties: title] <->> [entity: Cell, properties: title, imgPath] 

麻烦： 计数部分，他们的标题是工作，不能从关系获取对象细胞

感谢您的帮助......

Answer 1

这应该是可能的。事实上，我认为，如果你与sectionNameKeyPath设置为“section.title”创建FRC你可以使用“标准”表视图的数据源的方法和获取结果控制器委托方法：

// Fetch "Cell" entities: 
NSFetchRequest *request = [NSFetchRequest fetchRequestWithEntityName:@"Cell"]; 

// First sort descriptor for grouping the cells into sections, sorted by section title: 
NSSortDescriptor *sort1 = [NSSortDescriptor sortDescriptorWithKey:@"section.title" ascending:YES]; 
// Second sort descriptor for sorting the cells within each section: 
NSSortDescriptor *sort2 = [NSSortDescriptor sortDescriptorWithKey:@"title" ascending:YES]; 
request.sortDescriptors = [NSArray arrayWithObjects:sort1, sort2, nil]; 

NSFetchedResultsController *frc = [[NSFetchedResultsController alloc] 
             initWithFetchRequest:request 
             managedObjectContext:context 
              sectionNameKeyPath:@"section.title" 
                cacheName:nil]; 

（我假设你有一个反比关系section从细胞实体到科实体）