具有NSFetchedResultsController的UITableView保留没有对象的节的标题

Question

I've got a bunch of NSManagedObjects that are divided into sections in a UITableView.

[Section Header 0]
[NSManagedObject]
[NSManagedObject]
[NSManagedObject]
[Section Header 1]
[NSManagedObject]
[Section Header 2]
[NSManagedObject]
[NSManagedObject]
[NSManagedObject]

The user can edit the objects on a per-section basis, including deleting them. Say I delete the [NSManagedObject] in [Section 1] above. This updates my NSFetchedResultsController and removes both the row and the section, including the section header.

Is there a way to keep a blank section with any objects? I've considered putting in some code which sets a minimum count for sections, but the issue is that it won't be in sync with the NSFetchedResultsController. Adding an extra section would just add it to the bottom, but I'd like to add it after the first section, regardless of whether there are one or more sections after.

The objects are all server-driven, so I'd like to make so I won't have a lot of hardcoded sections in there.

Thanks.

Answer 1

You should include an attribute or a relationship in your data model to keep track of the sections. Seeing that you group your user, there must be a criterion that you can model in your data.

Then initialize the NSFetchedResultsController to with the appropriate sectionNameKeyPath . Use Apple's plain vanilla code to display section information, if any.

What you actually display in each section is still up to you. (It's what you put in your datasource methods). But at least you can have a consistent system of sections and grouping of objects.