如何在Flutter（DART）中访问其他类的方法？

我在脚手架中使用了颤振贴图，并且在脚手架小部件类中有一个名为“ showMyBottomSheet”的方法。点击地图并打开底部工作表时，用于执行此方法的地图。

但是，既然我已经将这两个文件分开了，则无法从map类访问脚手架有状态窗口小部件中的“ showMyBottomSheet”方法。

我该怎么做？我不应该分开吗？

我的主页-home.dart

class MyHomePage extends StatefulWidget {
  static const String route = '/';

  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  static const String route = '/';

  // Bottom sheet
  final _scaffoldKey = new GlobalKey<ScaffoldState>();

  dynamic showMyBottomSheet(LatLng latlang) {
    _scaffoldKey.currentState.showBottomSheet((context) {
      return new CustomBottomSheet();
    });
  }

  @override
  void initState() {
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
      key: _scaffoldKey,
      drawer: buildDrawer(context, route),
      body: new Column(
        children: [
          new CustomMap(),
        ],
      ),
    );
  }
}

地图小工具-flutterMap.dart

class Cuenter code herestomMap extends StatefulWidget {
  @override
  _CustomMapState createState() => new _CustomMapState();
}

class _CustomMapState extends State<CustomMap> {
  var markers = <Marker>[];

  @override
  Widget build(BuildContext context) {
    return new Flexible(
      child: new FlutterMap(
        options: new MapOptions(
            center: new LatLng(51.25, 30.5),
            zoom: 15.0,
            onTap: // I want to call showMyBottomSheet method (from home page) here
        ),
        layers: [
          new TileLayerOptions(
              urlTemplate:
              "https://maps.wikimedia.org/osm-intl/{z}/{x}/{y}.png",
              subdomains: ['a', 'b', 'c']),
        ],
      ),
    );
  }
}