primary property

Whether this is the primary scroll view associated with the parent PrimaryScrollController.

When this is true, the scroll view is scrollable even if it does not have sufficient content to actually scroll. Otherwise, by default the user can only scroll the view if it has sufficient content. See physics.

On iOS, this also identifies the scroll view that will scroll to top in response to a tap in the status bar.

Defaults to true when scrollDirection is Axis.vertical and controller is null.