Duplicate the way iMessage app loads old messages when scrolling up

Basically trying to find a way to duplicate the way iOS iMessage works:

  • when you load a conversation with a person it loads in the newest 50 or so messages
  • if you scroll up/back it comes to a break point where you have to force it to load more
  • there’s first a loading wheel, then when it loads the older messages, the position of the screen holds (this is super important)
  • the older messages now sit on top of the newest ones (50 or so load each time)

I pretty much have this working except for the screen holding it’s position when the new set loads, any thoughts?