How to minimize the groups in List-Grouping?

Hello,

I have a usecase wherein there is a list & when I click on a list item it should open another list with few items in it.

In this example SAPUI5 Explored it's already having a list which is grouped in to category. This suits my usecase very well except that I should be able to hide the list items of a particular group when not in need.

Is there any other control for this requirement? if not, how to achieve this?

Thanks,

Rashmi