Cocoa Bindings for hierarchical model

Question

I have a NSCollectionView based master-detail interface, where I want to display Boards in the master and Lists+Cards in the detail view.

Board, holds a

Answer 1

If each list is the representedObject for each view item in the collection view, then you can populate each popupButton with a readonly NSArray property dependent upon the cards array that is in each list. In the List class add arrangedCards as a property.

- (NSArray *)arrangedCards
{
    return [[self valueForKey:@"cards"] sortedArrayUsingDescriptors:
      [self arrangedCardsSortDescriptors]];
} 

Use the sort you want for the popup. This arranges by name.

- (NSArray *)arrangedCardsSortDescriptors
{
    NSSortDescriptor *sortByName = [[NSSortDescriptor alloc] initWithKey:
      @"name" ascending:YES];
    return @[sortByName];
}

Bind the Content of the popup to the NSCollectionViewItem.

Model Key Path is representedObject.arrangedCards.

Use representedObject.arrangedCards.name as the Content Values.