setState() for stateful widget-CodePudding

I want to setState my buttonbar widget in the other file. What can i do? -my code is true. I have any error. Just i want true setState.- But if i write DesktopHeader.desktopHeaderKey.currentState!.setState({}), it's null returning.

class DesktopHeader extends StatefulWidget {
  static GlobalKey<State> desktopHeaderKey = GlobalKey();
  const DesktopHeader({Key? key}) : super(key: key);
  @override
  _DesktopHeaderState createState() => _DesktopHeaderState();
}

class _DesktopHeaderState extends State<DesktopHeader> {
  @override
  Widget build(BuildContext context) {
    return butonBar();
  }

  Widget butonBar() { ... }
  }

CodePudding user response：

When starting DesktopHeader, do you start it with key? In that:

DesktopHeader(key: DesktopHeader.desktopHeaderKey)

CodePudding user response：

you can try return type DesktopHeader class

 final GlobalKey< State<DesktopHeader>> 
     globalKey = GlobalKey< State<DesktopHeader>>();