Chat implementation

[kusik16]

Hello. I want to use your library for chat. And I want to use the grouping of groups as dates for chats, and when loading new elements up (from the server), I can get the same message dates that were in the previous pagination. And I understood a little bit that I need to recalculate them every time, but won't the layout jump at the same time? And I did not quite understand how I need to set the exact number of my elements? Because in the element examples it is always greater than firstItemIndex.