是否可以从另一个小部件访问Stateful widget中的实例函数？

GlobalKey<MyWidgetState> myWidgetKey = GlobalKey<MyWidgetState>();

class MyWidget extends StatefulWidget {
  MyWidget({Key key}) : super(key: key);

  @override
  MyWidgetState createState() => MyWidgetState();
}

class MyWidgetState extends State<MyWidget> {
  void myFunction() {
    // 实例函数的实现
  }

  @override
  Widget build(BuildContext context) {
    // 构建小部件的UI
  }
}

class AnotherWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return RaisedButton(
      onPressed: () {
        MyWidgetState myWidgetState = myWidgetKey.currentState;
        myWidgetState.myFunction();
      },
      child: Text('调用StatefulWidget的实例函数'),
    );
  }
}