CollectionView reveal callback/promise

Hello,

Would it be possible for the [reveal method of the CollectionView](https://docs.tabris.com/3.4/api/CollectionView.html#revealindex-options) to return a promise?

If I want to [get the cell by item index](https://docs.tabris.com/3.4/api/CollectionView.html#cellbyitemindexitemindex), I need to wait until the cell is visible, and for that I need to wait for the reveal function, even if the animation is disabled or the cell will be null.

Is there a workaround this problem, other than a setTimeout?

Thank you!

Start with the CollectionView reveal method and the cellByItemIndex API described in the linked documentation. Trace how reveal makes a cell visible, including disabled animation and null-cell cases, then determine how completion should be exposed and verify that callers can wait before accessing the cell.

Written by the indexing model from the issue text.