Replied 7 September 2021, 7:06 pm EST
I'm afraid that ScrollPositionChanged event gets triggered on any change in position of the scroll bars(either horizontal or vertical) its doesn't provide any information on which scroll bar position has changed. If you wish to check which scroll bar position has changed you may add a scroll event to the FlexGrid using the addEventListener method and based on the position you can get the scrolled bar type.
You may refer to the sample link demonstrating the same:https://stackblitz.com/edit/js-ulif4x?file=index.js
Let us know if that's works for you.