> ## 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="ios"
    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>

```swift Signature theme={"system"}
DynamicFacetListConnector(
  searcher: Searcher,
  filterState: FilterState,
  orderedFacets: [AttributedFacets],
  selections: [Attribute: Set<String>],
  selectionModeForAttribute: [Attribute: SelectionMode],
  filterGroupForAttribute: [Attribute: FilterGroupDescriptor],
  controller: DynamicFacetListController
)
```

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

## About this widget

<DynamicFacets current="ios" />

### Requirements

Declare each facet attribute in [`attributesForFaceting`](/doc/api-reference/api-parameters/attributesForFaceting).
Use the [Algolia dashboard](/doc/guides/managing-results/refine-results/faceting/how-to/declaring-attributes-for-faceting-with-dashboard) or the API.

Configure the facet order with [`renderingContent.facetOrdering`](/doc/api-reference/api-parameters/renderingContent#param-facet-ordering).

Add each facet attribute to the query's [`facets`](/doc/api-reference/api-parameters/facets) property with `Searcher.request.query.facets`.

<Note>
  Dynamic facet list requires InstantSearch iOS v7.12.0 or later.
</Note>

## Example

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

```swift Swift icon=code expandable theme={"system"}
let searcher = HitsSearcher(appID: "ALGOLIA_APPLICATION_ID",
                           apiKey: "ALGOLIA_SEARCH_API_KEY",
                           indexName: "INDEX_NAME")
searcher.request.query.facets = ["brand", "color", "size", "country"]

let filterState = FilterState()
let dynamicFacetListController = DynamicFacetListTableViewController()

let dynamicFacetlistConnector = DynamicFacetListConnector(searcher: searcher,
                                                          filterState: filterState,
                                                          selectionModeForAttribute: [
                                                            "color": .multiple,
                                                            "country": .multiple
                                                          ],
                                                          filterGroupForAttribute: [
                                                            "brand": ("brand", .or),
                                                            "color" : ("color", .or),
                                                          ],
                                                          controller: dynamicFacetListController)

searcher.connectFilterState(filterState)
searcher.search()
```

## Parameters

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

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

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

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

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

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

<ResponseField name="controller" type="DynamicFacetListController">
  The controller that displays the ordered facets and handles selections.
</ResponseField>

## Low-level API

Use the following components to connect the dynamic facet list:

* [`Searcher`](/doc/api-reference/widgets/instantsearch/ios): runs searches.
* `FilterState`: stores the current filter state.
* `DynamicFacetListInteractor`: manages dynamic facet state and behavior.
* `DynamicFacetListController`: displays the ordered facets and handles user interactions.

```swift Swift icon=code expandable theme={"system"}
let searcher = HitsSearcher(appID: "ALGOLIA_APPLICATION_ID",
                            apiKey: "ALGOLIA_SEARCH_API_KEY",
                            indexName: "INDEX_NAME")
searcher.request.query.facets = ["brand", "color", "size", "country"]

let filterState = FilterState()
let dynamicFacetListController = DynamicFacetListTableViewController()

let dynamicFacetListInteractor = DynamicFacetListInteractor(selectionModeForAttribute: [
                                                              "color": .multiple,
                                                              "country": .multiple
                                                            ])

dynamicFacetListInteractor.connectSearcher(searcher)
dynamicFacetListInteractor.connectFilterState(filterState, filterGroupForAttribute: [
                                                             "brand": ("brand", .or),
                                                             "color" : ("color", .or),
                                                           ])
dynamicFacetListInteractor.connectController(dynamicFacetListController)

searcher.connectFilterState(filterState)
searcher.search()
```

## Customize the view

Use a built-in controller or use `DynamicFacetListController` to customize how the dynamic facet list appears and handles user interactions.

### UIKit

`DynamicFacetListTableViewController` is a built-in `UITableViewController` that conforms to the `DynamicFacetListController` protocol.

To use a `UICollectionView`, a third-party view, or custom behavior, create a controller that conforms to `DynamicFacetListController`.

#### `DynamicFacetListController` protocol

| Member                                                       | Description                        |
| ------------------------------------------------------------ | ---------------------------------- |
| `func setOrderedFacets(_ orderedFacets: [AttributedFacets])` | Updates the ordered facets.        |
| `func setSelections(_ selections: [Attribute: Set<String>])` | Updates the selected facet values. |
| `var didSelect: ((Attribute, Facet) -> Void)?`               | Runs when users select a facet.    |

### SwiftUI

`DynamicFacetListObservableController` conforms to `DynamicFacetListController` for SwiftUI.

Use its `orderedFacets` and `selections` properties and its `toggle` and `isSelected` methods to build a custom SwiftUI view.

#### Build a SwiftUI view

```swift Swift icon=code expandable theme={"system"}
struct ContentView: View {

  @ObservedObject var dynamicFacetListController: DynamicFacetListObservableController

  var body: some View {
    ScrollView {
      ForEach(dynamicFacetListController.orderedFacets, id: \.attribute) { orderedFacet in
        VStack(spacing: 0) {
          // Facet header
          ZStack {
            Color(.systemGray5)
            Text(orderedFacet.attribute.rawValue)
              .fontWeight(.semibold)
              .frame(maxWidth: .infinity, alignment: .leading)
              .padding(.horizontal, 5)
          }
          // Facet values
          ForEach(orderedFacet.facets, id: \.value) { facet in
            VStack(spacing: 0) {
              FacetRow(facet: facet,
                      isSelected: dynamicFacetListController.isSelected(facet, for: orderedFacet.attribute))
                .onTapGesture {
                  dynamicFacetListController.toggle(facet, for: orderedFacet.attribute)
                }
                .frame(minHeight: 44, idealHeight: 44, maxHeight: .infinity, alignment: .center)
                .padding(.horizontal, 5)
            }
          }
        }
      }
    }
  }
}
```