isScrollingNotifier property
final
This notifier's value is true if a scroll is underway and false if the scroll position is idle.
Listeners added by stateful widgets should be removed in the widget's State.dispose method.
This sample shows how you can trigger an auto-scroll, which aligns the last
partially visible fixed-height list item, by listening to this
notifier's value. This sort of thing can also be done by listening for
ScrollEndNotifications with a NotificationListener. An alternative
example is provided with ScrollEndNotification.
link
To create a local project with this code sample, run:
flutter create --sample=widgets.ScrollPosition.isScrollingNotifier.1 mysample
Implementation
final ValueNotifier<bool> isScrollingNotifier = ValueNotifier<bool>(false);