gistfile1.txt

import 'package:flutter/material.dart';

class TwoLevelListDemo extends StatelessWidget {
  static const String routeName = '/two-level-list';

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      appBar: new AppBar(title: new Text('Expand/collapse list control')),
      body: new Column(
        children: <Widget>[
          new Container(
            height: 56.0,
            child: new Material(
              elevation: 4,
              type: MaterialType.canvas,
              child: new Padding(
                padding: const EdgeInsets.symmetric(horizontal: 24.0),
                child: new Row(
                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
                  children: <Widget>[
                    new Text('foo'),
                    new Text('bar')
                  ]
                )
              )
            )
          ),
          new TwoLevelList(
            type: MaterialListType.oneLine,
            children: <Widget>[
              new TwoLevelListItem(title: new Text('Top')),
              new TwoLevelSublist(
                title: new Text('Sublist'),
                children: <Widget>[
                  new TwoLevelListItem(title: new Text('One')),
                  new TwoLevelListItem(title: new Text('Two')),
                  new TwoLevelListItem(title: new Text('Free')),
                  new TwoLevelListItem(title: new Text('Four'))
                ]
              ),
              new TwoLevelListItem(title: new Text('Bottom'))
            ]
          )
        ]
      )
    );
  }
}