CODE EXAMPLE FOR DART

flutter snackbar top

ScaffoldMessenger.of(context).showSnackBar(new SnackBar(
    content: Text('Snackbar message'),
    behavior: SnackBarBehavior.floating,
    shape: RoundedRectangleBorder(
      borderRadius: BorderRadius.circular(24),
    ),
    margin: EdgeInsets.only(
        bottom: MediaQuery.of(context).size.height - 100,
        right: 20,
        left: 20),
  ));