> ## Documentation Index
> Fetch the complete documentation index at: https://algolia.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Dynamic facet list

> Displays facets and facet values in the order returned by Algolia.

export const DynamicFacets = ({current}) => <div>
    <p>
      This widget displays matching refinement widgets in the order provided by{" "}
      <a className="link" href="/doc/api-reference/api-parameters/renderingContent#param-facet-ordering">
        <code>renderingContent.facetOrdering</code>
      </a>{" "}
      in the search response. 
    </p>

    <p>
      Configure the order with{" "}
      <a className="link" href={`/doc/guides/building-search-ui/ui-and-ux-patterns/facet-display/${current}`}>
        facet display
      </a>
      , override it with{" "}
      <a className="link" href="/doc/guides/managing-results/rules/rules-overview">
        Algolia Rules
      </a>
      , or generate it automatically with{" "}
      <a className="link" href="/doc/guides/algolia-ai/dynamic-facets">
        Dynamic Facets
      </a>
      . Dynamic Facets orders facets and facet values based on recent search
      data.
    </p>
  </div>;

export const FlavorSwitcher = ({current, baseHref = "", options = [], label = "InstantSearch framework"}) => {
  if (options.length === 0) {
    return <div className="not-prose" role="alert" style={{
      margin: "0.25rem 0 1.5rem",
      padding: "0.75rem",
      border: "1px solid #f59e0b",
      borderRadius: "0.625rem",
      color: "inherit",
      fontSize: "0.875rem"
    }}>
        FlavorSwitcher requires at least one option.
      </div>;
  }
  const selected = options.find(option => option.value === current) ?? options[0];
  return <div className="not-prose mint-flavor-switcher">
      <style>{`
        .mint-flavor-switcher {
          --mfs-bg: #ffffff;
          --mfs-bg-hover: #f4f4f5;
          --mfs-bg-current: #eef2ff;
          --mfs-border: #d4d4d8;
          --mfs-fg: #18181b;
          --mfs-muted: #71717a;
          --mfs-accent: #4f46e5;
          position: relative;
          width: min(100%, 19rem);
          margin: 0.25rem 0 1.5rem;
          color: var(--mfs-fg);
          font-size: 0.875rem;
          line-height: 1.25rem;
        }

        .dark .mint-flavor-switcher {
          --mfs-bg: #18181b;
          --mfs-bg-hover: #27272a;
          --mfs-bg-current: #272747;
          --mfs-border: #3f3f46;
          --mfs-fg: #fafafa;
          --mfs-muted: #a1a1aa;
          --mfs-accent: #a5b4fc;
        }

        .mint-flavor-switcher details {
          position: relative;
        }

        .mint-flavor-switcher summary {
          display: flex;
          min-height: 2.75rem;
          box-sizing: border-box;
          align-items: center;
          justify-content: space-between;
          gap: 0.75rem;
          padding: 0.625rem 0.75rem;
          border: 1px solid var(--mfs-border);
          border-radius: 0.625rem;
          background: var(--mfs-bg);
          color: var(--mfs-fg);
          cursor: pointer;
          font-weight: 600;
          list-style: none;
          transition: border-color 150ms ease, box-shadow 150ms ease;
        }

        .mint-flavor-switcher summary::-webkit-details-marker {
          display: none;
        }

        .mint-flavor-switcher summary:hover {
          border-color: var(--mfs-accent);
        }

        .mint-flavor-switcher summary:focus-visible {
          outline: 2px solid var(--mfs-accent);
          outline-offset: 2px;
        }

        .mint-flavor-switcher__label {
          overflow: hidden;
          text-overflow: ellipsis;
          white-space: nowrap;
        }

        .mint-flavor-switcher__chevron {
          flex: none;
          transition: transform 150ms ease;
        }

        .mint-flavor-switcher details[open] .mint-flavor-switcher__chevron {
          transform: rotate(180deg);
        }

        .mint-flavor-switcher__menu {
          position: absolute;
          z-index: 50;
          top: calc(100% + 0.375rem);
          left: 0;
          width: 100%;
          box-sizing: border-box;
          margin: 0;
          padding: 0.375rem;
          border: 1px solid var(--mfs-border);
          border-radius: 0.625rem;
          background: var(--mfs-bg);
          box-shadow: 0 12px 30px rgb(0 0 0 / 16%);
          list-style: none;
        }

        .mint-flavor-switcher__menu li {
          margin: 0;
          padding: 0;
        }

        .mint-flavor-switcher__option {
          display: grid;
          gap: 0.125rem;
          padding: 0.625rem 0.75rem;
          border-radius: 0.4rem;
          color: var(--mfs-fg);
          text-decoration: none;
        }

        .mint-flavor-switcher__option:hover {
          background: var(--mfs-bg-hover);
        }

        .mint-flavor-switcher__option:focus-visible {
          outline: 2px solid var(--mfs-accent);
          outline-offset: -2px;
        }

        .mint-flavor-switcher__option[aria-current="page"] {
          background: var(--mfs-bg-current);
          color: var(--mfs-accent);
        }

        .mint-flavor-switcher__name {
          font-weight: 600;
        }

        .mint-flavor-switcher__description {
          color: var(--mfs-muted);
          font-size: 0.8125rem;
        }

        @media (prefers-reduced-motion: reduce) {
          .mint-flavor-switcher summary,
          .mint-flavor-switcher__chevron {
            transition: none;
          }
        }
      `}</style>

      <details>
        <summary aria-label={`${label}: ${selected.label}`}>
          <span className="mint-flavor-switcher__label">{selected.label}</span>
          <svg className="mint-flavor-switcher__chevron" width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
            <path d="m6 9 6 6 6-6" />
          </svg>
        </summary>

        <ul className="mint-flavor-switcher__menu" aria-label={label}>
          {options.map(option => {
    const isCurrent = option.value === selected.value;
    const href = option.href ?? `${baseHref.replace(/\/$/, "")}/${encodeURIComponent(option.value)}`;
    return <li key={option.value}>
                <a className="mint-flavor-switcher__option" href={href} aria-current={isCurrent ? "page" : undefined}>
                  <span className="mint-flavor-switcher__name">
                    {option.label}
                  </span>
                  {option.description ? <span className="mint-flavor-switcher__description">
                      {option.description}
                    </span> : null}
                </a>
              </li>;
  })}
        </ul>
      </details>
    </div>;
};

<div className="mint-flavor-switcher-slot not-prose">
  <FlavorSwitcher
    current="android"
    baseHref="/doc/api-reference/widgets/dynamic-widgets"
    options={[
{ value: "js", label: "JavaScript", description: "InstantSearch.js" },
{ value: "react", label: "React", description: "React InstantSearch" },
{ value: "vue", label: "Vue", description: "Vue InstantSearch" },
{ value: "ios", label: "iOS", description: "InstantSearch iOS" },
{ value: "android", label: "Android", description: "InstantSearch Android" },
]}
  />
</div>

```kotlin Signature theme={"system"}
DynamicFacetListConnector(
    searcher: SearcherIndex,
    filterState: FilterState,
    orderedFacets: List<AttributedFacets>,
    selections: SelectionsPerAttribute,
    selectionModeForAttribute: Map<String, SelectionMode>,
    filterGroupForAttribute: Map<String, FilterGroupDescriptor>
)
```

<Card title="Explore example code" icon="github" href="https://github.com/algolia/instantsearch-android/tree/master/examples/android">
  Browse the example code on GitHub.
</Card>

## About this widget

<DynamicFacets current="android" />

### Requirements

Declare each facet attribute in [`attributesForFaceting`](/doc/api-reference/api-parameters/attributesForFaceting).

Configure the facet order in the [Algolia dashboard](/doc/guides/managing-results/refine-results/faceting/how-to/declaring-attributes-for-faceting-with-dashboard) or
with [`renderingContent`](/doc/api-reference/api-parameters/renderingContent).

Set the query's [`facets`](/doc/api-reference/api-parameters/facets) property and include each facet attribute to retrieve.

<Note>
  Dynamic facet list requires InstantSearch Android v2.1.1 or later.
</Note>

## Example

Create a `DynamicFacetListConnector`, set the query's facets, and run the initial search.

```kotlin Kotlin icon=code expandable theme={"system"}
class MyActivity : AppCompatActivity() {
    val searcher = HitsSearcher(
        applicationID = "ALGOLIA_APPLICATION_ID",
        apiKey = "ALGOLIA_SEARCH_API_KEY",
        indexName = "INDEX_NAME"
    )
    val filterState = FilterState()
    val color = "color"
    val country = "country"
    val brand = "brand"
    val size = "size"
    val dynamicFacets = DynamicFacetListConnector(
            searcher = searcher,
            filterState = filterState,
            selectionModeForAttribute = mapOf(
                    color to SelectionMode.Multiple,
                    country to SelectionMode.Multiple
            ),
            filterGroupForAttribute = mapOf(
                    brand to (brand to FilterOperator.Or),
                    color to (color to FilterOperator.Or),
            )
    )
    val connection = ConnectionHandler(dynamicFacets)

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        val dynamicFacetListView = DynamicFacetListAdapter(DynamicFacetListViewHolderImpl.Factory)
        connection += dynamicFacets.connectView(dynamicFacetListView)
        searcher.query = searcher.query.copy(facets = listOf(brand, color, size, country))
        searcher.searchAsync()
    }

    override fun onDestroy() {
        super.onDestroy()
        searcher.cancel()
        connection.clear()
    }
}
```

## Parameters

<ResponseField name="searcher" type="SearcherIndex" required>
  The [`Searcher`](/doc/api-reference/widgets/instantsearch/android) that runs searches.
</ResponseField>

<ResponseField name="filterState" type="FilterState" required>
  The [`FilterState`](/doc/api-reference/widgets/filter-state/android) that stores the current filters.
</ResponseField>

<ResponseField name="orderedFacets" type="List<AttributedFacets>" post={["default: []"]}>
  The initial ordered facets.
</ResponseField>

<ResponseField name="selections" type="SelectionsPerAttribute" post={["default: []"]}>
  Maps each facet attribute to its selected facet values.
</ResponseField>

<ResponseField name="selectionModeForAttribute" type="Map<String, SelectionMode>" post={["default: [:]"]}>
  Maps each facet attribute to its facet-value selection mode.
  The default mode is `Single`.
</ResponseField>

<ResponseField name="filterGroupForAttribute" type="Map<String, FilterGroupDescriptor>" post={["default: [:]"]}>
  Maps each facet attribute to the filter group that stores its filters in the filter state.
</ResponseField>

## View

<ParamField body="view" type="DynamicFacetListView" required>
  The view that renders the dynamic facet list.

  ```kotlin Kotlin icon=code theme={"system"}
  val facetListAdapter = FacetListAdapter(FacetListViewHolderImpl.Factory)
  val facetListPresenter = FacetListPresenterImpl(listOf(FacetSortCriterion.CountDescending, FacetSortCriterion.AlphabeticalAscending))
  facetListCategory.connectView(facetListAdapter, facetListPresenter)
  ```
</ParamField>

## Low-level API

Use the following components to connect the dynamic facet list:

* [`Searcher`](/doc/api-reference/widgets/instantsearch/android): runs searches.
* `FilterState`: stores the current filter state.
* `DynamicFacetsListViewModel`: manages dynamic facet state and behavior.

```kotlin Kotlin icon=code expandable theme={"system"}
class MyActivity : AppCompatActivity() {
    val searcher = HitsSearcher(
        applicationID = "ALGOLIA_APPLICATION_ID",
        apiKey = "ALGOLIA_SEARCH_API_KEY",
        indexName = "INDEX_NAME"
    )
    val filterState = FilterState()
    val color = "color"
    val country = "country"
    val brand = "brand"
    val size = "size"
    val dynamicFacetViewModel = DynamicFacetListViewModel(
          selectionModeForAttribute = mapOf(
                  color to SelectionMode.Multiple,
                  country to SelectionMode.Multiple
          )
  )
    val connection = ConnectionHandler(dynamicFacets)

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        connection += dynamicFacetViewModel.connectSearcher(searcher)
        connection += dynamicFacetViewModel.connectFilterState(filterState, mapOf(
                brand to (brand to FilterOperator.Or),
                color to (color to FilterOperator.Or))
        )
        // Your implementation of `DynamicFacetListView`
        val dynamicFacetListView = DynamicFacetListAdapter(DynamicFacetListViewHolderImpl.Factory)
        connection += dynamicFacets.connectView(dynamicFacetListView)
        searcher.query = searcher.query.copy(facets = listOf(brand, color, size, country))
        searcher.searchAsync()
    }

    override fun onDestroy() {
        super.onDestroy()
        searcher.cancel()
        connection.clear()
    }
}
```

## Customize the view

The `DynamicFacetListView` interface displays the ordered facets and handles user interactions.

Use this interface to provide a custom view:

```kotlin Kotlin icon=code theme={"system"}
// Implements DynamicFacetListView.
val myDynamicFacetListView = MyDynamicFacetListView() 
dynamicFacets.connectView(myDynamicFacetListView)
```

### Android views

`DynamicFacetListAdapter` is a built-in implementation of `DynamicFacetListView` that extends `ListAdapter`.

Pass a `DynamicFacetListViewHolder.Factory` implementation to the adapter:

```kotlin Kotlin icon=code theme={"system"}
// Implements DynamicFacetListViewHolder.Factory.
val factory = DynamicFacetListViewHolderImpl.Factory
val dynamicFacetListView = DynamicFacetListAdapter(factory)
dynamicFacets.connectView(dynamicFacetListView)
```

### Compose UI

`DynamicFacetListState` implements `DynamicFacetListView` for Compose UI.

Use its `facetOrder` and `facetSelections` properties and its `toggle` and `isSelected` functions to build a custom Compose UI.

#### Implementation example

```kotlin Kotlin icon=code expandable theme={"system"}
import com.algolia.client.model.search.FacetHits

@Composable
fun DynamicFacetsList(modifier: Modifier = Modifier, dynamicFacetListState: DynamicFacetListState) {
    LazyColumn(modifier) {
        dynamicFacetListState.facetOrder.forEach { (attribute, facets) ->
            item {
                Header(attribute = attribute)
            }
            items(facets) { facet ->
                FacetRow(
                    modifier = Modifier.fillMaxWidth(),
                    facet = facet,
                    isSelected = dynamicFacetListState.isSelected(facet, attribute),
                    onClick = { dynamicFacetListState.toggle(facet, attribute) }
                )
            }
        }
    }
}

@Composable
fun Header(modifier: Modifier = Modifier, attribute: String) {
    Text(modifier = modifier.padding(horizontal = 16.dp, vertical = 8.dp), text = attribute)
}

@Composable
fun FacetRow(modifier: Modifier = Modifier, facet: FacetHits, isSelected: Boolean, onClick: () -> Unit = {}) {
    Card(modifier = modifier, onClick = onClick) {
        Row(Modifier.padding(horizontal = 16.dp, vertical = 8.dp)) {
            Text(modifier = Modifier.weight(1f), text = facet.value)
            if (isSelected) Icon(Icons.Default.Check, contentDescription = null)
            Text(text = facet.count.toString())
        }
    }
}
```