ExpansionTiles 두 개 이상의 단계의 목록을 생성 할 수.

그림

 

 

 

수입 ' 패키지 : 플러터 / material.dart ' ; 

클래스 ExpansionTileSample이 StatelessWidget {확장 
  @Override 
  위젯 빌드 (BuildContext 컨텍스트를) { 
    반환  새 MaterialApp ( 
      : 집에 새로운 발판 ( 
        appBar : 새로운 AppBar ( 
          제목 : CONST 텍스트 ( ' ExpansionTile ' ), 
        ), 
        몸 : 새로운 ListView.builder ( 
          itemBuilder을 : ( BuildContext 컨텍스트 INT 인덱스) => 새로운  EntryItem (데이터 [인덱스),
          ITEMCOUNT : data.length입니다,
        ),
      ),
    );
  }
}

// One entry in the multilevel list displayed by this app.
class Entry {
  Entry(this.title, [this.children = const <Entry>[]]);
  final String title;
  final List<Entry> children;
}

// The entire multilevel list displayed by this app.
final List<Entry> data = <Entry>[
  new Entry('Chapter A',
    <Entry>[
      new Entry('Section A0',
        <Entry>[
          new Entry('Item A0.1'),
          new Entry('Item A0.2'),
          new Entry('Item A0.3'),
        ],
      ),
      new Entry('Section A1'),
      new Entry('Section A2'),
    ],
  ),
  new Entry('Chapter B',
    <Entry>[
      new Entry('Section B0'),
      new Entry('Section B1'),
    ],
  ),
  new Entry('Chapter C',
    <Entry>[
      new Entry('Section C0'),
      new Entry('Section C1'),
      new Entry('Section C2',
        <Entry>[
          new Entry('Item C2.0'),
          new Entry('Item C2.1'),
          new Entry('Item C2.2'),
          new Entry('Item C2.3'),
        ],
      ),
    ],
  ),
];

// Displays one Entry. If the entry has children then it's displayed
// with an ExpansionTile.
class EntryItem extends StatelessWidget {
  const EntryItem(this.entry);

  final Entry entry;

  Widget _buildTiles(Entry root) {
    if (root.children.isEmpty)
      return new ListTile(title: new Text(root.title));
    return new ExpansionTile(
      key: new PageStorageKey<Entry>(root),
      title: new Text(root.title),
      children: root.children.map(_buildTiles).toList(),
    );
  }

  @override
  Widget build(BuildContext context) {
    return _buildTiles(entry);
  }
}

void main() {
  runApp(new ExpansionTileSample());
}