> For the complete documentation index, see [llms.txt](https://gitbook.ziyuesinicization.site/filters-api/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://gitbook.ziyuesinicization.site/filters-api/advanced/registering-uncategorized-filter.md).

# Registering uncategorized filter

Filters API is a complete library.

{% hint style="success" %}
Filters API allows you to add filters for other mods (even vanilla). If so, registering the uncategorized filter to avoid some items disappearing is very important.
{% endhint %}

You can register an uncategorized filter for the tab. All items in the tab which not belong to any filter will be categorized to it.

A tab can have a single uncategorized filter only. If there are no other filters or no items are uncategorized, this filter will not appear on the screen.

Call `FilterBuilder.registerUncategorizedItemsFilter(ItemGroup)` to register the uncategorized filter.

```java
Filter FILTER = FilterBuilder.registerUncategorizedItemsFilter(CREATIVE_MODE_TAB);
```

## See also

{% embed url="<https://maven.ziyuesinicization.site/javadoc/releases/ziyue/filters/raw/ziyue/filters/FilterBuilder.html#registerUncategorizedItemsFilter(net.minecraft.item.ItemGroup)>" %}
The javadoc (1.16\~1.19.4)
{% endembed %}