TableViewCell中的CoreData相关数据

Question

I am working on a project with related entities in CoreData. I want to have a tableview with cells that show attributes of records from a related entity, but am struggling to find a good way to do this.

Here's the basics:

My custom TableViewCell has five things:

UILabel *eventTime
UILabel *person1Name
UIImageView *person1Image //storing a string
UILabel *person2Name
UIImageView *person2Image //storing a string

Event entity has a time, person1Name, and person2Name attributes and a to-many relationship to my Person entity.

Person entity has string attributes for name and image and a to-many relationship to my Events entity.

Events will always have two related person records.

Persons will be affiliated with many events.

In my cellForRowAtIndexPath, how do I configure the cell so that the related person attributes show for each event?

I was playing with this:

EventsTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"EventCell" forIndexPath:indexPath];
Event *event = [self.fetchedResultsController objectAtIndexPath:indexPath];
NSSet *persons = event.eventPersons;  //eventPersons is the NSSet in the NSManagedObject subclass…

// Configure the cell...

for (Player* p in persons) {
    if (p.firstName == event.person1Name) {
        cell.player1NameLabel.text = p.firstName;
        cell.player1ImageView.image = [UIImage imageWithContentsOfFile:p.playerImage];
    } else if (p.firstName == event.person2Name) {
        cell.player2NameLabel.text = p.firstName;
        cell.player2ImageView.image = [UIImage imageWithContentsOfFile:p.playerImage];
    }
}

But I may have multiple people with the same first name, so this fails to work properly in all cases. I don't want to store a bunch of duplicate information in the Event entity for comparing records and would prefer a more elegant way to grab the attributes of the two related person records in each cell.

Thanks.

Answer 1

You already have duplicate information in the storage of the names. But your problem is that they aren't unique.

So, change them to be unique (Ie Use a different identifier than the name) or use a different method of recording first and second (Ie Use an ordered relationship).