NSCollectionView with sections - like in iPhoto

Question

I\'d like to build a NSCollectionView similar to the one in iPhoto \'11. I want to group several pictures in section, and create a section header as well. The section header

Answer 1

Here is a similar sample:

Check this: https://developer.apple.com/library/mac/samplecode/TableViewPlayground/Introduction/Intro.html#//apple_ref/doc/uid/DTS40010727