If you need the UI effect like Apple's MacOS, if you want the box sliding is more cool, you can use my plugin to realize that. All the card items in my customized scroll box can always be showed in fixed number, just like the heroes selection in MOBA game. And you can use two buttons to select previous item or next item, that means my scroll box can be outdriven by code. By the way my focusing item is just more bigger than other items, if you need more fascinating effect, you can just modify the focusing part of my source.
