Collection View Dynamic Height in a Table View Cell

[tadeha]

Hello,

How can I re-size the collection view's height after each reload to fit the number of tags?
I know I can use collectionView.collectionViewLayout.collectionViewContentSize.height but I don't know where to put it. Is there any better way or please tell me where to put collectionView.collectionViewLayout.collectionViewContentSize.height to set collection's height constraint constant.

Thanks!