Dynamic Facet List
DynamicFacetListConnector( searcher: Searcher, filterState: FilterState, orderedFacets: [AttributedFacets], selections: [Attribute: Set<String>], selectionModeForAttribute: [Attribute: SelectionMode], filterGroupForAttribute: [Attribute: FilterGroupDescriptor], controller: DynamicFacetListController )
About this widget
DynamicFacetList is a view that displays the ordered list of facets and facet values. 
The order of groups and facet values in each group is defined by the corresponding settings of the index and may be altered by a Rule.
You can configure the facet merchandising through the corresponding index setting.
Learn how to set up ordering in the facet display guide.
Requirements
You must set the attributes for faceting and configure the facet order,
either using the dashboard) 
or with the API parameters attributesForFaceting 
and renderingContent.
You must also set the facets property of the query with Searcher.request.query.facets and provide the facet attributes you want to retrieve.
You must use at least InstantSearch iOS version 7.12.0 to use Dynamic Facet List.
Examples
Instantiate a DynamicFacetListConnector, set the query facets and launch an initial search on its searcher.
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let searcher = HitsSeacher(appID: "YourApplicationID", 
                           apiKey: "YourSearchOnlyAPIKey", 
                           indexName: "YourIndexName")
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
| Parameter | Description | 
|---|---|
          
            searcher
          
         | 
        
           
                
                type: Searcher
                
               
              
                
                        Required
                
               
          The   | 
      
          
            filterState
          
         | 
        
           
                
                type: FilterState
                
               
              
                
                        Required
                
               
          The   | 
      
          
            orderedFacets
          
         | 
        
           
                
                type: [AttributedFacets]
                
               
              
                
                  default: []
                
               
              
                
                    Optional
                
               
          The ordered list of attributed facets.  | 
      
          
            selections
          
         | 
        
           
                
                type: [Attribute: Set<String>]
                
               
              
                
                  default: []
                
               
              
                
                    Optional
                
               
          The mapping between a facet attribute and a set of selected facet values.  | 
      
          
            selectionModeForAttribute
          
         | 
        
           
                
                type: [Attribute: SelectionMode]
                
               
              
                
                  default: [:]
                
               
              
                
                    Optional
                
               
          The mapping between a facet attribute and a facet values selection mode. If not provided, the default selection mode is   | 
      
          
            filterGroupForAttribute
          
         | 
        
           
                
                type: [Attribute: FilterGroupDescriptor]
                
               
              
                
                  default: [:]
                
               
              
                
                    Optional
                
               
          The mapping between a facet attribute and a descriptor of a filter group where the corresponding facet filters are stored in the filter state.  | 
      
          
            controller
          
         | 
        
           
                
                type: DynamicFacetListController
                
               
              
                
                    Optional
                
               
          
  | 
      
Low-level API
If you want to fully control the DynamicFacetList components and connect them manually, you can use the following components:
Searcher: theSearcherthat handles your searches.FilterState: the current state of the filters.DynamicFacetListInteractor: dynamic facet list business logicDynamicFacetListController: controller presenting the ordered list of facets and handling the user interaction
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let searcher = HitsSearcher(appID: "YourApplicationID", 
                            apiKey: "YourSearchOnlyAPIKey", 
                            indexName: "YourIndexName")
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()
Customizing your view
UIKit
InstantSearch iOS provides the DynamicFacetListTableViewController, which is the UITableViewController subclass that implements the DynamicFacetListController protocol.
If you want to use another component, such as a UICollectionView or a third-party view, or if you want to introduce some custom behavior to the already provided UIKit component, you can create your own controller conforming to the DynamicFacetListController protocol.
Protocol
func setOrderedFacets(_ orderedFacets: [AttributedFacets])
Update the list of the ordered attributed facets
func setSelections(_ selections: [Attribute: Set<String>])
Update the facet selections
var didSelect: ((Attribute, Facet) -> Void)?
Closure to trigger when user selects a facet
SwiftUI
InstantSearch iOS provides the DynamicFacetListObservableController, an implementation of the DynamicFacetListController protocol adapted for usage with SwiftUI. 
It provides orderedFacets and selections properties with convenient toggle and isSelected functions which allow you to implement your own SwiftUI view.
Implementation example
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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)
            }
          }
        }
      }
    }
  }
  
}