my_list_item.dart

class _MyListItem extends StatelessWidget {
  final Item item;

  _MyListItem(this.item, {Key key}) : super(key: key);

  //with states_rebuilder you can get the current them without BuildContext
  final textTheme = RM.theme.textTheme.headline6;

  void _displaySnackBar() {
    //with states_rebuilder you can get the active ScaffoldState without
    // explicitly using the BuildContext
    RM.scaffold.showSnackBar(
      SnackBar(
        content: Text('error.message'),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Dismissible(
      key: Key('${item.id}'),
      onDismissed: (_) {
        // Get the global CatalogState ReactiveModel
        RM.get<CatalogState>().setState(
          // Invoke deleteItem
          (currentState) => CatalogState.deleteItem(
            currentState,
            item,
          ),
          onError: (context, error) {
            // Display SnackBar
            _displaySnackBar();
          },
        );
      },
      child: Padding(
        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
        child: LimitedBox(
          maxHeight: 48,
          child: Row(
            children: [
              AspectRatio(
                aspectRatio: 1,
                child: Container(
                  color: item.color,
                ),
              ),
              SizedBox(width: 24),
              Expanded(
                child: Text(item.name, style: textTheme),
              ),
              SizedBox(width: 24),
              _AddButton(item: item),
            ],
          ),
        ),
      ),
    );
  }
}