ScrollableList({Key key, double initialScrollOffset, Axis scrollDirection: Axis.vertical, ViewportAnchor scrollAnchor: ViewportAnchor.start, ScrollListener onScrollStart, ScrollListener onScroll, ScrollListener onScrollEnd, SnapOffsetCallback snapOffsetCallback, Key scrollableKey, @required double itemExtent, bool itemsWrap: false, EdgeInsets padding, Iterable<Widget> children: const [] })

Creats a scrollable list of children that have equal size.

The scrollDirection, scrollAnchor, and itemExtent arguments must not be null.

Source 

ScrollableList({
  Key key,
  this.initialScrollOffset,
  this.scrollDirection: Axis.vertical,
  this.scrollAnchor: ViewportAnchor.start,
  this.onScrollStart,
  this.onScroll,
  this.onScrollEnd,
  this.snapOffsetCallback,
  this.scrollableKey,
  @required this.itemExtent,
  this.itemsWrap: false,
  this.padding,
  this.children: const <Widget>[],
}) : super(key: key) {
  assert(scrollDirection != null);
  assert(scrollAnchor != null);
  assert(itemExtent != null);
}