[How to use] How to control scroll behavior when adding messages at the end of a chat list with bidirectional pagination?

[Holofox]

Platforms

Android, iOS

Description

I'm using ChatScrollObserver to maintain scroll position in a chat interface with bidirectional pagination (loading messages in both directions — up for older messages and down for newer messages).

My code

Current Implementation:

Following the Chat Observer guide, I've set up scroll position preservation when new messages are added.

This works correctly when the user is not at the end of the list.

Try do it

The Issue:
When the user is at the very end of the list (the last message is visible), and new messages are loaded, the scroll position preservation doesn't work as expected. The view jumps instead of maintaining the user's position relative to the content they were viewing.

If the number of new messages is less than fixedPositionOffset and the user is at the end of the list, scrolling down is the expected behavior. However, if more messages than fixedPositionOffset are added, I don’t want the list to scroll. How can I achieve this?

[LinXunFeng]

The fixedPositionOffset corresponds to scroll offset (scrollController.offset), not number of new messages. It only maintains scroll position when the current offset exceeds this value. If you set it to 5 like in the guide but the scroll offset is 0 (at the very end of the list ), the feature won't work. Try setting it to -1 instead.

[Holofox]

@LinXunFeng, got it, thanks!