createScrollPosition method Null safety

  1. @override
ScrollPosition createScrollPosition(
  1. ScrollPhysics physics,
  2. ScrollContext context,
  3. ScrollPosition? oldPosition

Creates a ScrollPosition for use by a Scrollable widget.

Subclasses can override this function to customize the ScrollPosition used by the scrollable widgets they control. For example, PageController overrides this function to return a page-oriented scroll position subclass that keeps the same page visible when the scrollable widget resizes.

By default, returns a ScrollPositionWithSingleContext.

The arguments are generally passed to the ScrollPosition being created:


ScrollPosition createScrollPosition(ScrollPhysics physics, ScrollContext context, ScrollPosition? oldPosition) {
  return _PagePosition(
    physics: physics,
    context: context,
    initialPage: initialPage,
    keepPage: keepPage,
    viewportFraction: viewportFraction,
    oldPosition: oldPosition,