UI components

PubNub Chat Components for iOS provide easy-to-use building blocks to create chat applications for various use cases with different functionalities and customizable looks.

Available components include:

• ChannelList
• MemberList
• MessageList
• MessageInput

Component theming

Default ThemeTemplate provides structural and appearance configurations for each component and its sub-components. Light and dark modes for each theme are supported automatically through adaptive elements based on the current system-wide appearance settings.

Most appearance properties use Combine to asynchronously update the corresponding bound View elements. You can access the shared ThemeTemplate through the themeProvider property of any ChatProvider instance.

ChannelList

UIViewController that displays a list of stored Channel objects. It can represent all channels of the application, only channels joined by the current user, all channels available to be joined, or any other type of NSFetchedResultsController made against stored channel data.

Parameters

You can initialize the ChannelList view model using the following parameters.

Name	Type	Default value	Description
provider	ChatProvider	n/a	The ChatProvider instance to be used inside this component.
fetchedEntities	NSFetchedResultsController	n/a	The data type and query options used to populate the component.
componentTheme	ChannelListComponentTheme?	The ChannelList theme sourced from ChatProvider.	The configurable theme used for the component. If you provide a custom object, you must maintain it outside of ChatProvider.

View model

The view model is used to configure both the main UIViewController for the component, the channel data, and lay out any sub-components.

To override core functionality, you can either subclass the view model or implement override blocks to replace specific key functionalities.

The default ChannelListComponentViewModel is configured to display the default channel memberships of the current user, sorted by the type and name of the channel.

Component population

ChatProvider can be extended to return a configured NSFetchedResultsController, and this object ensures the component always displays the most recent data. NSFetchedResultsController can contain any type of stored data related to a channel, and can be sorted and sectioned based on any channel property.

Default example

By default, the list is populated by any channel of which the current user is a member. The list is divided into multiple sections based on the channel type, and each section is sorted by the name of the channel.

open func channelMembershipsFrom(
  userId: String, sectionedByType: Bool
) -> NSFetchedResultsController<ManagedEntities.Member> {

  let request = ManagedEntities.Member.membershipsBy(userId: userId)

  request.sortDescriptors = [
    NSSortDescriptor(key: "channel.type", ascending: false),
    NSSortDescriptor(key: "channel.name", ascending: true)
  ]
  request.relationshipKeyPathsForPrefetching = ["channel"]

  return fetchedResultsControllerProvider(
    fetchRequest: request,
    sectionKeyPath: sectionedByType ? "channel.type": nil,
    cacheName: nil
  )
}

You can create a view model composed of the above default NSFetchedResultsController and ChannelListComponentTheme using this ChatProvider extension method:

open func senderMembershipsChannelListComponentViewModel(
  sectionedByType: Bool = true,
  customTheme: ChannelListComponentTheme? = nil
) -> ChannelListComponentViewModel<ModelData, ManagedEntities> {
  return ChannelListComponentViewModel(
    provider: self,
    fetchedEntities: channelMembershipsFrom(userId: senderID, sectionedByType: sectionedByType),
    customTheme: customTheme ?? self.themeProvider.template.channelListComponent
  )
}

Properties

The ChannelList view model provides outlets for the following properties after initialization:

Name	Type	Default value	Description
provider	ChatProvider	n/a	A ChatProvider instance to be used inside this component.
fetchedEntities	NSFetchedResultsController	n/a	The data type and query options used to populate the component.
componentTheme	ChannelListComponentTheme	The ChannelList theme sourced from ChatProvider.	The configurable theme used for the component.
leftBarButtonNavigationItems	(UIViewController, ChannelListComponentViewModel) -> [UIBarButtonItem]	nil	Views that appear on the left side of the navigation bar.
rightBarButtonNavigationItems	(UIViewController, ChannelListComponentViewModel) -> [UIBarButtonItem]	nil	Views that appear on the right side of the navigation bar.
customNavigationTitleView	(ChannelListComponentViewModel) -> UIView?	nil	The custom view that's used inside the navigation bar title.
customNavigationTitleString	(ChannelListComponentViewModel) -> AnyPublisher<String?, Never>	nil	The custom String publisher that's used inside the navigation bar title if a view isn't provided.
customChannelCellViewModel	(ChannelListComponentViewModel, Channel) -> ChannelCellComponentViewModel	nil	The cell view model that's be used instead of the default model found inside the theme.
configureFetchedResultsController	(NSFetchedResultsController) -> Void	nil	An outlet to customize the channel data query before the data is fetched.

You can configure the message items inside the list with the data found inside ManagedChannelViewModel:

public protocol ManagedChannelViewModel {
  associatedtype Entity: ManagedChatChannel
  associatedtype MemberViewModel: ManagedMemberViewModel & Hashable
  associatedtype MessageViewModel: ManagedMessageViewModel & Hashable

  var pubnubId: String { get }
  var managedObjectId: NSManagedObjectID { get }

  var channelNamePublisher: AnyPublisher<String, Never> { get }
  var channelDetailsPublisher: AnyPublisher<String?, Never> { get }
  var channelAvatarUrlPublisher: AnyPublisher<URL?, Never> { get }
  var channelTypePublisher: AnyPublisher<String, Never> { get }
  var channelCustomPublisher: AnyPublisher<Data, Never> { get }

  var membershipPublisher: AnyPublisher<Set<MemberViewModel>, Never> { get }
  var memberCountPublisher: AnyPublisher<Int, Never> { get }
  var presentMemberCountPublisher: AnyPublisher<Int, Never> { get }

  var messagesPublisher: AnyPublisher<Set<MessageViewModel>, Never> { get }
  var oldestMessagePublisher: AnyPublisher<MessageViewModel?, Never> { get }
}

Theming

You can configure the ChannelListComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
controllerType	ComponentViewController	No	Default class type that is used when creating new UIViewController instances.
backgroundColor	UIColor	Yes	View Controller’s background color.
navigationTitleView	BasicComponentTheme?	Yes	Theming for UIView found on the UINavigationItem component.
collectionViewTheme	CollectionViewComponentTheme	Yes	Theming for UICollectionView found on the UIViewController component.
sectionHeaderLabel	LabelComponentTheme	Yes	Theming for UILabel you can attach to the UICollectionReusableView section Header-type.
cellTheme	MemberListCellComponentTheme	Yes	Theming for UICollectionViewCell found on the UIViewController component.

You can configure the CollectionViewComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
viewType	UICollectionView.Type	No	Default class type that is used when creating new UICollectionView instances.
layoutType	CollectionViewLayoutComponent.Type	No	Default class type that is used when creating new UICollectionViewLayout instances.
headerType	UICollectionReusableView.Type	No	Default class type that is used when creating new UICollectionView section headers.
footerType	UICollectionReusableView.Type	No	Default class type that is used when creating new UICollectionView section footers.
backgroundColor	UIColor	Yes	View background color.
scrollViewTheme	ScrollViewComponentTheme	Yes	Theming for the UIScrollView properties of UICollectionView.
refreshControlTheme	RefreshControlTheme?	Yes	Theming for the UIRefreshControl properties of UICollectionView.
prefetchIndexThreshold	Int?	Yes	List index that when scrolled past triggers a remote sync request to fetch additional data to be stored into the local database.
isPrefetchingEnabled	Bool	No	A Boolean value that indicates whether cell and data pre-fetching are enabled. This allows for more efficient pre-fetching, but isn't required.

You can configure the ChannelListCellComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
cellType	CollectionViewCellComponent.Type	No	Default class type that is used when creating new UICollectionViewCell instances.
backgroundColor	UIColor?	Yes	View's background color.
highlightColor	UIColor?	Yes	View's background color during highlighted state.
selectedColor	UIColor?	Yes	View's background color during selected state.
itemTheme	BasicComponentTheme	Yes	Theming for the sub-views of the channel list cell.

You can configure the BasicComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
imageView	ImageComponentTheme	Yes	Theming for the User avatar UIImageView
primaryLabel	LabelComponentTheme	Yes	Theming for the primary UILabelView that can be displayed on the channel list cell.
secondaryLabel	LabelComponentTheme	Yes	Theming for the secondary UILabelView that can be displayed on the channel list cell.
tertiaryLabel	LabelComponentTheme	Yes	Theming for the tertiary UILabelView that can be displayed on the channel list cell.
quaternaryLabel	LabelComponentTheme	Yes	Theming for the quaternary UILabelView that can be displayed on the channel list cell.

You can configure the ImageComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
customType	ImageComponentView.Type	No	Default class type that is used when creating new UIImageView instances.
localImage	UIImage?	Yes	Locally sourced UIImage you can use as a placeholder while fetching remote images.
cornerRadius	CGFloat	Yes	The radius to use when drawing rounded corners for the layer’s background.
margin	UIEdgeInsets	Yes	The default spacing to use when laying out content in the view.

You can configure the LabelComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
textFont	UIFont	Yes	Font of the text.
textColor	UIColor	Yes	Color of the text.
textAlignment	NSTextAlignment	Yes	Technique for aligning the text.
adjustsFontForContentSizeCategory	Bool	Yes	Boolean that determines whether the text's font size is reduced to fit inside the bounds of the UILabelView.

Default

The default implementation is available through ChannelListComponentTheme.pubnubDefaultGroupChannelList which is composed of the following values:

ChannelListComponentTheme(
  controllerType: CollectionViewComponent.self,
  backgroundColor: .clear,
  navigationTitleView: BasicComponentTheme(
    imageView: ImageComponentTheme(
      customType: PubNubAvatarComponentView.self,
      localImage: AppearanceTemplate.Image.avatar,
      diameterSize: 42,
      margin: .init(top: .zero, left: .zero, bottom: .zero, right: 5.0)
    ),
    primaryLabel: LabelComponentTheme(
      customType: PubNubLabelComponentView.self,
      textFont: AppearanceTemplate.Font.title2.bold,
      textColor: AppearanceTemplate.Color.label,
      adjustsFontForContentSizeCategory: true,
      textAlignment: .natural,
      textMargin: .zero
    )
  ),
  collectionViewTheme: CollectionViewComponentTheme(
    viewType: UICollectionView.self,
    layoutType: TableCollectionViewLayout.self,
    headerType: ReusableLabelViewComponent.self,
    footerType: ReusableLabelViewComponent.self,
    backgroundColor: .systemBackground,
    isPrefetchingEnabled: true,
    scrollingBounces: false,
    alwaysBounceVertical: false,
    showsHorizontalScrollIndicator: false,
    keyboardDismissMode: .interactive,
    automaticallyAdjustsScrollIndicatorInsets: true,
    contentInsetAdjustmentBehavior: .always
  ),
  headerLabel: LabelComponentTheme(
    customType: PubNubLabelComponentView.self,
    textFont: AppearanceTemplate.Font.title1.bold,
    textColor: AppearanceTemplate.Color.label,
    adjustsFontForContentSizeCategory: true,
    textAlignment: .natural,
    textMargin: .zero
  ),
  itemTheme: ChannelListCellComponentTheme(
    customType: CollectionViewContainerCellComponent.self,
    viewModelType: ChannelCellViewModel.self,
    backgroundColor: .clear,
    highlightColor: .clear,
    selectedColor: .systemGray4,
    itemTheme: BasicComponentTheme(
      imageView: ImageComponentTheme(
        customType: PubNubAvatarComponentView.self,
        localImage: AppearanceTemplate.Image.avatar,
        diameterSize: 30,
        margin: .init(top: .zero, left: 10.0, bottom: .zero, right: 5.0)
      ),
      primaryLabel: LabelComponentTheme(
        customType: PubNubLabelComponentView.self,
        textFont: AppearanceTemplate.Font.caption1,
        textColor: AppearanceTemplate.Color.label,
        adjustsFontForContentSizeCategory: true,
        textAlignment: .natural,
        textMargin: .zero
      ),
      secondaryLabel: LabelComponentTheme(
        customType: PubNubLabelComponentView.self,
        textFont: AppearanceTemplate.Font.caption2,
        textColor: AppearanceTemplate.Color.secondaryLabel,
        adjustsFontForContentSizeCategory: true,
        textAlignment: .natural,
        textMargin: .zero
      )
    )
  )
)

Actions

This component supports the following UI interactions:

Name	Type	Default value	Description
componentDidLoad	(UIViewController, ChannelListComponentViewModel) -> Void	nil	An action called when the component view is loaded.
componentWillAppear	(UIViewController, ChannelListComponentViewModel) -> Void	nil	An action called when the component view appears on the screen.
componentWillDisappear	(UIViewController, ChannelListComponentViewModel) -> Void	nil	An action called when the component view disappears from the screen.
didSelectChannel	(UIViewController, ChannelListComponentViewModel, ChatChannel) -> Void	Default MessageList component	An action called when a user taps a list item.

Example

The following example shows how an action can be configured after creating a view model. didSelectChannel creates a default MessageList component from the selected channel and displays it from the current ChannelList component.

let channelViewModel = chatProvider
  .senderMembershipsChannelListComponentViewModel()

channelViewModel.didSelectChannel = { (controller, viewModel, channel) in

  // Prepare Message List View
  guard let component = try? viewModel.provider
          .messageListComponentViewModel(for: channel.id)
          .configuredComponentView() else { return }

  // Display it from the current controller in the primary content view
  controller.show(component, sender: nil)
}

MemberList

UIViewController that displays a list of stored Member and User objects. It can represent all members of a specific channel, only other users that are currently present in the application, a sectioned list of present and non-present members, or any other type of NSFetchedResultsController made against stored member data.

Parameters

You can initialize the MemberList view model using the following parameters.

Name	Type	Default value	Description
provider	ChatProvider	n/a	A ChatProvider instance to be used inside this component.
selectedChannelId	String	n/a	The channel identifier used during a member query.
fetchedEntities	NSFetchedResultsController	n/a	The data type and query options used to populate the component.
componentTheme	MemberListComponentTheme?	The MemberList theme sourced from ChatProvider.	The configurable theme used for the component. If you provide a custom object, you must maintain it outside of ChatProvider.

View model

The view model is used to configure both the main UIViewController for the component, the member data, and lay out any sub-components.

To override core functionality, you can either subclass the view model or implement override blocks to replace specific key functionalities.

The default MemberListComponentViewModel is configured to display the users that are members of a specific channel, sorted by their presence status and name.

Component population

ChatProvider can be extended to return a configured NSFetchedResultsController, and this object ensures the component always displays the most recent data. NSFetchedResultsController can contain any type of stored data related to a member, and can be sorted and sectioned based on any member property.

Default example

By default, the list is populated by any user that's a member of the provided channel. The list is sorted based on the presence status and the name of the user.

open func userMembersFrom(
  channelId: String,
  excludingSender: Bool = false
) -> NSFetchedResultsController<ManagedEntities.Member> {

  let request = ManagedEntities.Member.membersBy(
    channelID: channelId,
    excludingUserId: excludingSender ? senderID : nil,
    onlyPresent: true
  )

  request.sortDescriptors = [
    NSSortDescriptor(key: "user.name", ascending: true)
  ]

  request.relationshipKeyPathsForPrefetching = ["user"]

  return fetchedResultsControllerProvider(
    fetchRequest: request,
    sectionKeyPath: nil,
    cacheName: nil
  )
}

You can create a view model composed of the above default NSFetchedResultsController and MemberListComponentTheme using this ChatProvider extension method:

open func memberListComponentViewModel(
  channelId: String,
  customTheme: MemberListComponentTheme? = nil
) -> MemberListComponentViewModel<ModelData, ManagedEntities> {
  return MemberListComponentViewModel(
    provider: self,
    fetchedEntities: userMembersFrom(channelId: channelId),
    customTheme: customTheme ?? self.themeProvider.template.memberListComponent
  )
}

Properties

The MemberList view model provides outlets for the following properties after initialization:

Name	Type	Default value	Description
provider	ChatProvider	n/a	A ChatProvider instance to be used inside this component.
fetchedEntities	NSFetchedResultsController	n/a	The data type and query options used to populate the component.
componentTheme	ChannelListComponentTheme	The ChannelList theme sourced from ChatProvider.	The configurable theme used for the component.
selectedChannelId	String	n/a	The channel identifier used during the member query.
leftBarButtonNavigationItems	(UIViewController, MemberListComponentViewModel) -> [UIBarButtonItem]	nil	Views that appear on the left side of the navigation bar.
rightBarButtonNavigationItems	(UIViewController, MemberListComponentViewModel) -> [UIBarButtonItem]	nil	Views that appear on the right side of the navigation bar.
customNavigationTitleView	(MemberListComponentViewModel) -> UIView?	nil	The custom view that's used inside the navigation bar title.
customNavigationTitleString	(MemberListComponentViewModel) -> AnyPublisher<String?, Never>	nil	The custom String publisher that's used inside the navigation bar title if a view isn't provided.
customMemberCellViewModel	(MemberListComponentViewModel, Member) -> MemberCellComponentViewModel	nil	The cell view model that's used instead of the default model found inside the theme.
configureFetchedResultsController	(NSFetchedResultsController) -> Void	nil	The outlet to customize the member data query before the data is fetched.

You can configure the message items inside the list with the data found inside ManagedMemberViewModel:

public protocol ManagedMemberViewModel {
  associatedtype Entity: ManagedChatMember
  associatedtype ChannelViewModel: ManagedChannelViewModel
  associatedtype UserViewModel: ManagedUserViewModel

  var managedObjectId: NSManagedObjectID { get }

  var isPresentPublisher: AnyPublisher<Bool, Never> { get }

  var channelViewModel: ChannelViewModel { get }
  var userViewModel: UserViewModel { get }
}

Theming

You can configure the MemberListComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
controllerType	ComponentViewController	No	Default class type that is used when creating new UIViewController instances.
backgroundColor	UIColor	Yes	View Controller’s background color.
navigationTitleView	BasicComponentTheme?	Yes	Theming for UIView found on the UINavigationItem component.
collectionViewTheme	CollectionViewComponentTheme	Yes	Theming for UICollectionView found on the UIViewController component.
sectionHeaderLabel	LabelComponentTheme	Yes	Theming for UILabel you can attach to the UICollectionReusableView section Header-type.
cellTheme	MemberListCellComponentTheme	Yes	Theming for UICollectionViewCell found on the UIViewController component.

You can configure the CollectionViewComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
viewType	UICollectionView.Type	No	Default class type that is used when creating new UICollectionView instances.
layoutType	CollectionViewLayoutComponent.Type	No	Default class type that is used when creating new UICollectionViewLayout instances.
headerType	UICollectionReusableView.Type	No	Default class type that is used when creating new UICollectionView section headers.
footerType	UICollectionReusableView.Type	No	Default class type that is used when creating new UICollectionView section footers.
backgroundColor	UIColor	Yes	View background color.
scrollViewTheme	ScrollViewComponentTheme	Yes	Theming for UIScrollView properties of UICollectionView.
refreshControlTheme	RefreshControlTheme?	Yes	Theming for UIRefreshControl properties of UICollectionView.
prefetchIndexThreshold	Int?	Yes	List index that when scrolled past triggers a remote sync request to fetch additional data to be stored into the local database.
isPrefetchingEnabled	Bool	No	A Boolean value that indicates whether cell and data pre-fetching are enabled. This allows for more efficient pre-fetching, but isn't required.

You can configure the MemberListCellComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
cellType	CollectionViewCellComponent.Type	No	Default class type that is used when creating new UICollectionViewCell instances.
backgroundColor	UIColor?	Yes	View's background color.
highlightColor	UIColor?	Yes	View's background color during highlighted state.
selectedColor	UIColor?	Yes	View's background color during selected state.
itemTheme	BasicComponentTheme	Yes	Theming for the sub-views of the member list cell..

You can configure the BasicComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
imageView	ImageComponentTheme	Yes	Theming for the User avatar UIImageView
primaryLabel	LabelComponentTheme	Yes	Theming for the primary UILabelView you can display on the member list cell.
secondaryLabel	LabelComponentTheme	Yes	Theming for the secondary UILabelView you can display on the member list cell.
tertiaryLabel	LabelComponentTheme	Yes	Theming for the tertiary UILabelView you can display on the member list cell.
quaternaryLabel	LabelComponentTheme	Yes	Theming for the quaternary UILabelView you can display on the member list cell.

You can configure the ImageComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
customType	ImageComponentView.Type	No	Default class type that is used when creating new UIImageView instances.
localImage	UIImage?	Yes	Locally sourced UIImage you can use as a placeholder while fetching remote images.
cornerRadius	CGFloat	Yes	The radius to use when drawing rounded corners for the layer’s background.
margin	UIEdgeInsets	Yes	The default spacing to use when laying out content in the view.

You can configure the LabelComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
textFont	UIFont	Yes	Font of the text.
textColor	UIColor	Yes	Color of the text.
textAlignment	NSTextAlignment	Yes	Technique for aligning the text.
adjustsFontForContentSizeCategory	Bool	Yes	Boolean that determines whether the text's font size is reduced to fit inside the bounds of UILabelView.

Default

The default implementation is available through MemberListComponentTheme.pubnubDefaultGroupMemberList which is composed of the following values:

MemberListComponentTheme(
  controllerType: CollectionViewComponent.self,
  backgroundColor: .clear,
  navigationTitleView: BasicComponentTheme(
    imageView: ImageComponentTheme(
      customType: PubNubAvatarComponentView.self,
      localImage: AppearanceTemplate.Image.avatar,
      diameterSize: 42,
      margin: .init(top: .zero, left: .zero, bottom: .zero, right: 5.0)
    ),
    primaryLabel: LabelComponentTheme(
      customType: PubNubLabelComponentView.self,
      textFont: AppearanceTemplate.Font.title2.bold,
      textColor: AppearanceTemplate.Color.label,
      adjustsFontForContentSizeCategory: true,
      textAlignment: .natural,
      textMargin: .zero
    )
  ),
  collectionViewTheme: CollectionViewComponentTheme(
    viewType: UICollectionView.self,
    layoutType: TableCollectionViewLayout.self,
    headerType: ReusableLabelViewComponent.self,
    footerType: ReusableLabelViewComponent.self,
    backgroundColor: .systemBackground,
    isPrefetchingEnabled: true,
    scrollingBounces: false,
    alwaysBounceVertical: false,
    showsHorizontalScrollIndicator: false,
    keyboardDismissMode: .interactive,
    automaticallyAdjustsScrollIndicatorInsets: true,
    contentInsetAdjustmentBehavior: .always
  ),
  headerLabel: LabelComponentTheme(
    customType: PubNubLabelComponentView.self,
    textFont: AppearanceTemplate.Font.title1.bold,
    textColor: AppearanceTemplate.Color.label,
    adjustsFontForContentSizeCategory: true,
    textAlignment: .natural,
    textMargin: .zero
  ),
  itemTheme: MemberListCellComponentTheme(
    customType: CollectionViewContainerCellComponent.self,
    viewModelType: MemberCellViewModel.self,
    backgroundColor: .clear,
    highlightColor: .clear,
    selectedColor: .clear,
    itemTheme: BasicComponentTheme(
      imageView: ImageComponentTheme(
        customType: PubNubAvatarComponentView.self,
        localImage: AppearanceTemplate.Image.avatar,
        diameterSize: 30,
        margin: .init(top: .zero, left: 10.0, bottom: .zero, right: 5.0)
      ),
      primaryLabel: LabelComponentTheme(
        customType: PubNubLabelComponentView.self,
        textFont: AppearanceTemplate.Font.caption1,
        textColor: AppearanceTemplate.Color.label,
        adjustsFontForContentSizeCategory: true,
        textAlignment: .natural,
        textMargin: .zero
      ),
      secondaryLabel: LabelComponentTheme(
        customType: PubNubLabelComponentView.self,
        textFont: AppearanceTemplate.Font.caption2,
        textColor: AppearanceTemplate.Color.secondaryLabel,
        adjustsFontForContentSizeCategory: true,
        textAlignment: .natural,
        textMargin: .zero
      )
    )
  )
)

Actions

This component supports the following UI interactions:

Name	Type	Default value	Description
componentDidLoad	(UIViewController, MemberListComponentViewModel) -> Void	nil	An action called when the component view is loaded.
componentWillAppear	(UIViewController, MemberListComponentViewModel) -> Void	nil	An action called when the component view appears on the screen.
componentWillDisappear	(UIViewController, MemberListComponentViewModel) -> Void	nil	An action called when the component view disappears from the screen.
didSelectMember	(UIViewController, MemberListComponentViewModel, ChatMember) -> Void	nil	An action called when a user taps a list item.

Example

The following example shows how an action can be configured after creating a view model.

componentDidLoad is called when the component view first loads. The following example shows how to call PubNub HereNow presence and automatically store the response in the local database.

let memberViewModel = provider
  .memberListComponentViewModel(channelId: "stored-channel-id")

memberViewModel.componentDidLoad = { controller, viewModel in
  viewModel.provider.dataProvider.syncHereNow(
    .init(channels: [viewModel.selectedChannel.pubnubId]),
    completion: nil
  )
}

MessageList

UIViewController that displays a list of stored message objects. It's primarily used to fetch historical messages for a channel, including user names, avatars, times of sending, and rich message types (links, images).

Parameters

You can initialize the MemberList view model using the following parameters.

Name	Type	Default value	Description
provider	ChatProvider	n/a	A ChatProvider instance to be used inside this component.
author	User	n/a	The User that represents the current application user.
selectedChannel	Channel	n/a	The channel of the displayed messages.
fetchedEntities	NSFetchedResultsController	n/a	The data type and query options used to populate the component.
componentTheme	MessageListComponentTheme?	The MessageList theme sourced from ChatProvider.	The configurable theme used for the component. If you provide a custom object, you must maintain it outside of ChatProvider.

View model

The view model is used to configure both the main UIViewController for the component, the member data, and lay out any sub-components.

To override core functionality, you can either subclass the view model or implement override blocks to replace specific key functionalities.

The default MessageListComponentViewModel is configured to display the messages of a particular channel sorted by the time a given message was sent.

Component population

ChatProvider can be extended to return a configured NSFetchedResultsController, and this object ensures the component always displays the most recent data. NSFetchedResultsController can contain any type of stored data related to a message, and can be sorted and sectioned based on any message property.

Default example

By default, the list is populated by any channel of which the current user is a member. The list will be divided into multiple sections based on the channel type, and each section is sorted by the name of the channel.

open func messagesFrom(
  pubnubChannelId: String
) -> NSFetchedResultsController<ManagedEntities.Message> {

  let request = ManagedEntities.Message.messagesBy(pubnubChannelId: pubnubChannelId)

  request.sortDescriptors = [
    NSSortDescriptor(key: "dateCreated", ascending: true)
  ]

  request.relationshipKeyPathsForPrefetching = ["sender"]

  return fetchedResultsControllerProvider(
    fetchRequest: request,
    sectionKeyPath: nil,
    cacheName: nil
  )
}

You can create a view model composed of the above default NSFetchedResultsController and MessageListComponentTheme using this ChatProvider extension method:

open func messageListComponentViewModel(
  for pubnubChannelId: String,
  customTheme: MessageListComponentTheme? = nil
) throws -> MessageListComponentViewModel<ModelData, ManagedEntities> {
  let sender = try fetchSender()

  guard let channel = try fetchChannel(byPubNubId: pubnubChannelId) else {
    throw ChatError.missingRequiredData
  }

  return MessageListComponentViewModel(
    provider: self,
    sender: sender,
    selectedChannel: channel,
    fetchedMessages: messagesFrom(pubnubChannelId: pubnubChannelId),
    componentTheme: customTheme ?? themeProvider.template.messageListComponent
  )
}

Channel ID storage

You must store the channel matching pubnubChannelId locally before calling the messageListComponentViewModel() method.

Properties

You can configure the MessageList view model using the following parameters.

Name	Type	Default	Description
provider	ChatProvider	n/a	A ChatProvider instance to be used inside this component.
author	User		The User that represents the current application user.
selectedChannel	Channel	n/a	The channel of the displayed message.
fetchedEntities	NSFetchedResultsController	n/a	The data type and query options used to populate the component.
componentTheme	MessageListComponentTheme	The MessageList theme sourced from ChatProvider.	The configurable theme used for the component.
leftBarButtonNavigationItems	(UIViewController, MessageListComponentViewModel) -> [UIBarButtonItem]	nil	Views that appear on the left side of the navigation bar.
rightBarButtonNavigationItems	(UIViewController, MessageListComponentViewModel) -> [UIBarButtonItem]	nil	Views that appear on the right side of the navigation bar.
customNavigationTitleView	(MessageListComponentViewModel) -> UIView?	nil	The custom view that's used inside the navigation bar title.
customNavigationTitleString	(MessageListComponentViewModel) -> AnyPublisher<String?, Never>	nil	The custom String publisher that's used inside the navigation bar title if a view isn't provided.
configureFetchedResultsController	(NSFetchedResultsController) -> Void	nil	The outlet to customize the message data query before the data is fetched.

You can configure the message items inside the list with the data found inside ManagedChannelViewModel:

public protocol ManagedMessageViewModel {
  associatedtype Entity: ManagedChatMessage
  associatedtype ChannelViewModel: ManagedChannelViewModel
  associatedtype UserViewModel: ManagedUserViewModel

  var pubnubId: Timetoken { get }
  var managedObjectId: NSManagedObjectID { get }

  var messageContentPublisher: AnyPublisher<MessageContent, Error> { get }
  var messageCustomPublisher: AnyPublisher<Data, Never> { get }

  var messageTextContentPublisher: AnyPublisher<String?, Never>? { get }
  var messageLinkContentPublisher: AnyPublisher<URL?, Never>? { get }
  var messageImageContentPublisher: AnyPublisher<URL?, Never>? { get }
  var messageJSONContentPublisher: AnyPublisher<AnyJSON?, Never>? { get }

  var messageCustomPublisher: AnyPublisher<Data, Never> { get }

  var messageDateCreatedPublisher: AnyPublisher<Date, Never> { get }

  var userViewModel: UserViewModel { get }
  var channelViewModel: ChannelViewModel { get }
}

Theming

You can configure the MessageListComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
controllerType	ComponentViewController.Type	No	Default class type that is used when creating new UIViewController instances.
backgroundColor	UIColor?	Yes	View Controller’s background color.
collectionViewTheme	CollectionViewComponentTheme	Yes	Theming for UICollectionView found on the UIViewController component.
incomingItemTheme	MessageListCellComponentTheme	Yes	Theming for messages that are sent from users other than the current user.
authorItemTheme	MessageListCellComponentTheme?	Yes	Theming for messages that are sent from the current user.
typingIndicatorCellTheme	TypingIndicatorCellTheme	Yes	Theming for UICollectionViewCell that's displayed when another member is typing.

You can configure the MessageListCellComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
textMessageContentCellType	CollectionViewCellComponent.Type	No	Default class for the UICollectionViewCell specific to text based messages.
richMessageContentCellTypes	[MessageContentType: CollectionViewCellComponent.Type]	No	Dictionary that maps UICollectionViewCell class types to known rich message content types.
backgroundColor	UIColor?	Yes	View's background color.
highlightColor	UIColor?	Yes	View's background color during highlighted state.
selectedColor	UIColor?	Yes	View's background color during selected state.
alignment	UICollectionViewCell.Alignment	Yes	Vertical list edge the message is anchored to.
maxWidthPercentage	CGFloat	Yes	Maximum width a Cell spans inside the message list frame.
bubbleContainerTheme	BubbleComponentTheme	Yes	Theming for the bubble view container you can wrap around message content.
contentTextTheme	TextViewComponentTheme	Yes	Theming for UITextView that displays message text content.
contentLinkTheme	LinkViewComponentTheme	Yes	Theming for LPLinkView that displays message URL content.
itemTheme	BasicComponentTheme	Yes	Theming for the accessory views around the message content.
dateFormatter	DateFormatter	Yes	DataFormatter used when displaying message dates.

You can configure the TypingIndicatorCellTheme theme using the following parameters.

Name	Type	Auto update on change	Description
cellType	CollectionViewCellComponent.Type	No	Default class for UICollectionViewCell when creating typing indicator cells.
contentViewType	UIView	No	Default class for contentView inside the UICollectionViewCell typing indicator.
backgroundColor	UIColor?	Yes	View's background color.
highlightColor	UIColor?	Yes	View's background color during highlighted state.
selectedColor	UIColor?	Yes	View's background color during selected state.
alignment	UICollectionViewCell.Alignment	Yes	The vertical list edge contentViewType is anchored to.
primaryContentColor	UIColor?	Yes	Primary color by the contentViewType view.
secondaryContentColor	UIColor?	Yes	Secondary color used by the contentViewType view.
animationEnabled	Bool	No	Whether the typing indicator is animated.
pulsing	Bool	No	Whether the typing indicator animation pulses.
bounces	Bool	No	Whether the typing indicator animation bounces.
bounceDelay	TimeInterval	No	Delay between each distinct sub-view's bounce animation.
bounceOffset	CGFloat	No	Distance each distinct sub-view bounces during its animation.
fades	Bool	No	Whether the typing indicator animation fades as it animates.

Default

The default implementation is available through MessageInputComponentTheme.pubnubGroupChat which is composed of the following values:

MessageListComponentTheme(
  controllerType: CollectionViewComponent.self,
  backgroundColor: .systemBackground,
  messageInputComponent: .pubnubGroupChat,
  collectionViewTheme:  CollectionViewComponentTheme(
    layoutType: ChatLayout.self,
    backgroundColor: .secondarySystemBackground,
    scrollViewTheme: .enabled,
    refreshControlTheme: .init(
      pullToRefreshTitle: .init(string: "Pull to Refresh"),
      pullToRefreshTintColor: nil
    ),
    prefetchIndexThreshold: 35,
    isPrefetchingEnabled: false
  ),
  incomingItemTheme: MessageListCellComponentTheme(
    textMessageContentCellType: MessageListItemCell.self,
    richMessageContentCellTypes: [
      .link: MessageLinkContentCell.self
    ],
    backgroundColor: .clear,
    highlightColor: .clear,
    selectedColor: .clear,
    alignment: .leading,
    maxWidthPercentage: 0.65,
    bubbleContainerTheme: BubbleComponentTheme(
      alignment: .leading,
      containerType: .tailed,
      backgroundColor: .systemBlue,
      tailSize: 5,
      layoutMargin: UIEdgeInsets(top: 8, left: 16, bottom: 8, right: 16)
    ),
    contentTextTheme: TextViewComponentTheme(
      customType: UITextView.self,
      backgroundColor: .clear,
      textColor: .black,
      textFont: AppearanceTemplate.Font.body,
      usesStandardTextScaling: false,
      dataDetectorTypes: .all,
      linkTextAttributes: [:],
      isEditable: false,
      isExclusiveTouch: false,
      scrollView: .disabled,
      textContainerInset: .zero
    ),
    contentLinkTheme: LinkViewComponentTheme(
      cacheProvider: InMemoryLinkMetadataCache.shared,
      layoutMargin: UIEdgeInsets(top: 8, left: 16, bottom: 8, right: 16)
    ),
    itemTheme: .pubnubGroupChannelList,
    dateFormatter: .messageInline
  ),
  authorItemTheme: nil,
  typingIndicatorCellTheme: AnimatedTypingIndicatorCellTheme(
    cellType: IMessageTypingIndicatorCell.self,
    contentViewType: IMessageTypingBubbleView.self,
    backgroundColor: .clear,
    highlightColor: .clear,
    selectedColor: .clear,
    primaryContentColor: .systemGray5,
    secondaryContentColor: .systemGray2,
    animationEnabled: true,
    pulsing: true,
    bounces: true,
    bounceDelay: 0.33,
    bounceOffset: 0.25,
    fades: true
  )
)

Actions

This component supports the following UI interactions:

Name	Type	Default value	Description
componentDidLoad	(UIViewController, MemberListComponentViewModel) -> Void	nil	Action called when the component view is loaded into memory. Maps to viewDidLoad() of the component view.
componentWillAppear	(UIViewController, MemberListComponentViewModel) -> Void	nil	Action called when the component view is about to be added to a view hierarchy. Maps to viewWillAppear(_:) of the component view.
componentWillDisappear	(UIViewController, MemberListComponentViewModel) -> Void	nil	Action called when the component view is removed from the view hierarchy. Maps to viewWillDisappear(_:) of the component view.

MessageInput

UIView that can be used to display an interactive UITextView with an optional, customizable UIButton used for sending the String input.

Component dependency

Unlike the other components that can be used as standalone view controllers, the message input should be treated as a sub-component. It's added as a sub-view or accessoryInput view of the UIViewController of another component.

Parameters

MessageInputComponent is the base class for the component. It can be sub-classed to add additional functionality or to include a third-party input bar. You can initialize the component through MessageInputComponentViewModel.

Name	Type	Default value	Description
provider	ChatProvider	n/a	ChatProvider instance to be used inside this component.
selectedChannel	Channel	n/a	Channel used when sending messages.
componentTheme	MessageInputComponentTheme?	The MessageInput theme sourced from ChatProvider.	The configurable theme used for the component. If you provide a custom object, you must maintain it outside of ChatProvider.

View model

The view model is used to configure both the main UIView for the component, the configuration of any sub-views, and the interaction between the MessageInputComponent and MessageListComponent.

To override core functionality, you can either subclass the view model or implement override blocks to replace specific key functionalities.

The default MessageInputComponentViewModel is configured based on the configurations found inside MessageInputComponentTheme.

Properties

The MessageInput view model provides outlets for the following properties after initialization:

Name	Type	Default	Description
provider	ChatProvider	n/a	ChatProvider instance to be used inside this component.
selectedChannel	Channel	n/a	Channel used when sending messages.
componentTheme	@Published MessageInputComponentTheme	The MessageInput theme sourced from ChatProvider.	The configurable theme used for the component.
typingMemberIds	@Published Set<String>	[]	Set of member PubNub identifiers that are currently typing on the channel. An empty Set means no one is currently typing.

Theming

You can configure the MessageInputComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
viewType	MessageInputComponent	No	Default class type that is used when creating new view instances.
backgroundColor	UIColor?	Yes	View’s background color.
placeholderText	String?	Yes	Text that appears whens the user hasn't entered the text.
placeholderTextColor	UIColor?	Yes	Placeholder text's color.
placeholderTextFont	UIFont?	Yes	Placeholder text's font.
textInputTheme	InputTextViewComponentTheme	Yes	Theming for UITextView used as the input view.
sendButtonTheme	ButtonComponentTheme	Yes	Theming for UIButton responsible for sending message input.
typingIndicatorService	TypingIndicatorService	No	Service that coordinates typing indicator events across all channels.
publishTypingIndicator	Bool	Yes	Whether typing indicator signals are sent to other chat users.
displayTypingIndicator	Bool	Yes	Whether typing indicator signals are displayed from other chat users.

You can configure the ButtonComponentTheme theme using the following parameters.

Name	Type	Auto update on change	Description
backgroundColor	UIColor?	Yes	View’s background color.
tintColor	UIColor?	Yes	Tint color to apply to the button title and image.
title	ButtonTitleStateTheme	Yes	Title during normal button state.
titleHighlighted	ButtonTitleStateTheme	Yes	Title during highlighted button state.
titleFont	UIFont?	Yes	Font of the button text.
image	ButtonImageStateTheme	Yes	Image during normal button state.
imageHighlighted	ButtonImageStateTheme	Yes	Image during highlighted button state.

You can configure the ButtonTitleStateTheme theme using the following parameters.

Name	Type	Auto update on change	Description
title	String?	Yes	Title that the button displays.
attributedTitle	NSAttributedString?	Yes	Styled text that the button displays.
titleColor	UIColor?	Yes	Color of the text.
titleShadowColor	UIColor?	Yes	Shadow color of the text.

You can configure the ButtonImageStateTheme theme using the following parameters.

Name	Type	Auto update on change	Description
image	UIImage?	Yes	Image used for a button state.
backgroundImage	UIImage?	Yes	Background image used for a button state.

Default

The default implementation is available through MessageInputComponentTheme.pubnubGroupChat which is composed of the following values:

MessageInputComponentTheme(
  viewType: MessageInputBarComponent.self,
  backgroundColor: .secondarySystemBackground,
  placeholderText: "Type Message",
  placeholderTextColor: .systemGray2,
  placeholderTextFont: AppearanceTemplate.Font.body,
  textInputTheme: InputTextViewComponentTheme(
    customType: UITextView.self,
    backgroundColor: .tertiarySystemBackground,
    textColor: .systemGray2,
    textFont: AppearanceTemplate.Font.body,
    usesStandardTextScaling: true,
    dataDetectorTypes: .all,
    linkTextAttributes: [:],
    isEditable: true,
    isExclusiveTouch: false,
    scrollView: .enabled,
    textContainerInset: .zero,
    typingAttributes: [:],
    autocapitalizationType: .sentences,
    autocorrectionType: .default,
    spellCheckingType: .default,
    smartQuotesType: .default,
    smartDashesType: .default,
    smartInsertDeleteType: .default,
    keyboardType: .default,
    keyboardAppearance: .default,
    textContentType: nil
  ),
  sendButton: ButtonComponentTheme(
    backgroundColor: .clear,
    tintColor: .systemBlue,
    title: .empty,
    titleHighlighted: .empty,
    titleFont: AppearanceTemplate.Font.caption1,
    image: ButtonImageStateTheme(
      image: UIImage(systemName: "paperplane.fill")?.rotate(degree: 45)?.withTintColor(.systemBlue),
      backgroundImage: nil
    ),
    imageHighlighted: .empty
  ),
  typingIndicatorService: .shared,
  publishTypingIndicator: true,
  displayTypingIndicator: true
)

Actions

This component supports the following UI interactions.

Name	Type	Default value	Description
messageWillSend	(MessageInputComponentViewModel, ChatMessage) -> ChatMessage	nil	Closure that's called before sending a message. Allows you to mutate the message that is sent.
messageDidSend	(MessageInputComponentViewModel, ChatMessage, Future<ChatMessage, Error>) -> Void	nil	Closure that's called after the message was sent. You can use Future to track the transmission of the message and handle any Error that might be returned.

Example

Let's see how to configure an action after creating a view model.

messageWillSend is called when the user is attempting to send a new message. The following example shows how to store the message before sending so it appears on the MessageList component faster:

let messageInputViewModel = try provider
  .messageInputComponentViewModel(channelId: "stored-channel-id")

messageInputViewModel.messageWillSend = { viewModel, message in

  viewModel.provider.dataProvider.load(messages: [message])

  return message
}