# updateItem method Null safety

1. @override

FaderModel updateItem(

1. FaderModel model,
2. ListedItemModel oldItem,
3. ListedItemModel newItem

)
override

## Implementation

    @override
    FaderModel updateItem(
        FaderModel model, ListedItemModel oldItem, ListedItemModel newItem) {
      List<ListedItemModel> currentItems =
          model.items == null ? [] : model.items!;
      var index = currentItems.indexOf(oldItem);
      if (index != -1) {
        var newItems = currentItems.map((e) => e).toList();
        newItems[index] = newItem;
        var newModel = model.copyWith(items: newItems);
        return newModel;
      } else {
        throw Exception("Could not find $oldItem");
      }
    }