gistfile1.txt

@implementation AvailableSceneView : CPImageView
{
}

- (void)setRepresentedObject:(id)anObject
{
    [self setImage:anObject];
}

@end

////// OR

@implementation CPControl (CollectionView)

- (void)setRepresentedObject:(id)anObject
{
    [self setObjectValue:anObject];
}

@end

gistfile2.txt

- somewhere
{
    item = [[CPCollectionViewItem alloc] init];
    [item setView:[[AvailableSceneView alloc] init]];
    //etc.

    [collectionView setDelegate:self];
    [collectionView setItemPrototype:item];
}


- (void)collectionViewDidChangeSelection:(CPCollectionView)aCollectionView 
{
    //grab the new selected index, do something with it
}

- (void)collectionView:(CPCollectionView)aCollectionView dragTypesForItemsAtIndexes:(CPIndexSet)indexes
{
    //return drag types
}

- (void)collectionView:(CPCollectionView)aCollectionView dataForItemsAtIndexes:(CPIndexSet)indexes forType:(CPString)aType
{
    //return the data of this type at this index
}