the "inspector" screen is not available for this applacation

Question

class _BottomNavigationBar extends StatelessWidget {
  const _BottomNavigationBar({
    Key? key,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return SafeArea(
      top: false,
      bottom: true,
      left: true,
      child: Row(
        mainAxisAlignment: MainAxisAlignment.spaceAround,
        children: [
          _BottomNavigationBar(),
          _BottomNavigationBar(),
          _BottomNavigationBar(),
          _BottomNavigationBar(),
        ],
      ),
    );
  }
}

class _NavigationBarItem extends StatelessWidget {
  const _NavigationBarItem({super.key});

  @override
  Widget build(BuildContext context) {
    return SafeArea(child: Text('item'));
  }

i am meeting this mistake in this window
i did a lot ways but they didnot work they didnt work