how to disable float stack in flutter

Scaffold(
    resizeToAvoidBottomPadding: false,
    body: body,
    appBar: appBar,
);

  bool isKeyboardVisible = false;

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

    KeyboardVisibilityNotification().addNewListener(
      onChange: (bool visible) {
        isKeyboardVisible = visible;
      },
    );
  }