Como implementar a função delete ?

class _ContactItemState extends State<_ContactItem> {
  final ContactDao _dao = ContactDao();
  bool isNotTaped = true;
  @override
  Widget build(BuildContext context) {
    return Card(
      color: Colors.green[100],
      child: SingleChildScrollView(
        child: ListTile(
          title: Text(
            widget.contact.name,
            style: const TextStyle(
              fontSize: 24.0,
            ),
          ),
          subtitle: Text(
            widget.contact.accountNumber.toString(),
            style: const TextStyle(
              fontSize: 16.0,
            ),
          ),
          trailing: IconButton(
            icon: const Icon(Icons.delete),
            iconSize: 30,
            color: (isNotTaped ? Colors.green[400] : Colors.red[400]),
            onPressed: () {
              setState(() {
                _dao.delete(id);
                isNotTaped = !isNotTaped;
              });
            },
          ),
        ),
      ),
    );
  }
}