TwoLevelList constructor

const TwoLevelList({Key key, List<Widget> children: const [], MaterialListType type: MaterialListType.twoLine, EdgeInsetsGeometry padding })

Creates a scrollable list of items that can expand and collapse.

The type argument must not be null.

Implementation 

const TwoLevelList({
  Key key,
  this.children = const <Widget>[],
  this.type = MaterialListType.twoLine,
  this.padding,
}) : assert(type != null),
     super(key: key);