Getting the index of the first visible section

[pr-Mais]

I don't know if I can relate to this as an issue, but I really need to have this feature as I tried many solutions, I have a list and need to scroll to a specific section when I navigate to the list page, I got this done using this package which was so easy and amazing, but now I need to change the app bar title as I scroll down or up to match the first visible section title in my list! I tried to wrap my section table view inside a NotificationListener, and measured the offsets of scrolling manually, which is not only great cause my list items aren't same height... but I get a value, when I write setState() to update the appbarIndex value so it renders the title in my appbar it breaks! I can't scroll anymore until I remove setState(), do you have any solution for this?

thanks in advance!