subscribeScroll method

void subscribeScroll(
  1. ScrollPosition position,
  2. VoidCallback listener
)

Subscribes listener to position for the session's lifetime: wheel/trackpad/second-finger scrolls move content under a stationary pointer, and the autoscroll ticker's own jumpTo notifies this same listener, giving one re-resolution path for every scroll source. detachAll unsubscribes.

Implementation

void subscribeScroll(ScrollPosition position, VoidCallback listener) {
  _subscribedPosition = position;
  _scrollListener = listener;
  position.addListener(listener);
}