Class EventTimeline

constructor

• new EventTimeline(eventTimelineSet: EventTimelineSet): EventTimeline

  Construct a new EventTimeline

  An EventTimeline represents a contiguous sequence of events in a room.

  As well as keeping track of the events themselves, it stores the state of the room at the beginning and end of the timeline, and pagination tokens for going backwards and forwards in the timeline.

  In order that clients can meaningfully maintain an index into a timeline, the EventTimeline object tracks a 'baseIndex'. This starts at zero, but is incremented when events are prepended to the timeline. The index of an event relative to baseIndex therefore remains constant.

  Once a timeline joins up with its neighbour, they are linked together into a doubly-linked list.

  Parameters

  • eventTimelineSet: EventTimelineSet

    the set of timelines this is part of

  Returns EventTimeline

paginationRequests

Static ReadonlyBACKWARDS

Static ReadonlyFORWARDS

addEvent

• addEvent(event: MatrixEvent, options: IAddEventOptions): void

  Add a new event to the timeline, and update the state

  Parameters

  • event: MatrixEvent

    new event
  • options: IAddEventOptions

    addEvent options

  Returns void

fork

• fork(direction: Direction): EventTimeline

  Creates an independent timeline, inheriting the directional state from this timeline.

  Parameters

  • direction: Direction

    EventTimeline.BACKWARDS to get the state at the start of the timeline; EventTimeline.FORWARDS to get the state at the end of the timeline.

  Returns EventTimeline

  the new timeline

forkLive

• forkLive(direction: Direction): EventTimeline

  Forks the (live) timeline, taking ownership of the existing directional state of this timeline. All attached listeners will keep receiving state updates from the new live timeline state. The end state of this timeline gets replaced with an independent copy of the current RoomState, and will need a new pagination token if it ever needs to paginate forwards.

  Parameters

  • direction: Direction

    EventTimeline.BACKWARDS to get the state at the start of the timeline; EventTimeline.FORWARDS to get the state at the end of the timeline.

  Returns EventTimeline

  the new timeline

getBaseIndex

• getBaseIndex(): number

  Get the base index.

  This is an index which is incremented when events are prepended to the timeline. An individual event therefore stays at the same index in the array relative to the base index (although note that a given event's index may well be less than the base index, thus giving that event a negative relative index).

  Returns number

getEvents

• getEvents(): MatrixEvent[]

  Get the list of events in this context

  Returns MatrixEvent[]

  An array of MatrixEvents

getFilter

• getFilter(): undefined | Filter

  Get the filter for this timeline's timelineSet (if any)

  Returns undefined | Filter

  filter

getNeighbouringTimeline

• getNeighbouringTimeline(direction: Direction): null | EventTimeline

  Get the next timeline in the series

  Parameters

  • direction: Direction

    EventTimeline.BACKWARDS to get the previous timeline; EventTimeline.FORWARDS to get the next timeline.

  Returns null | EventTimeline

  previous or following timeline, if they have been joined up.

getPaginationToken

• getPaginationToken(direction: Direction): null | string

  Get a pagination token

  Parameters

  • direction: Direction

    EventTimeline.BACKWARDS to get the pagination token for going backwards in time; EventTimeline.FORWARDS to get the pagination token for going forwards in time.

  Returns null | string

  pagination token

getRoomId

• getRoomId(): null | string

  Get the ID of the room for this timeline

  Returns null | string

  room ID

getState

• getState(direction: Direction): undefined | RoomState

  Get the room state at the start/end of the timeline

  Parameters

  • direction: Direction

    EventTimeline.BACKWARDS to get the state at the start of the timeline; EventTimeline.FORWARDS to get the state at the end of the timeline.

  Returns undefined | RoomState

  state at the start/end of the timeline

getTimelineSet

• getTimelineSet(): EventTimelineSet

  Get the timelineSet for this timeline

  Returns EventTimelineSet

  timelineSet

initialiseState

• initialiseState(
      stateEvents: MatrixEvent[],
      __namedParameters?: IInitialiseStateOptions,
  ): void

  Initialise the start and end state with the given events

  This can only be called before any events are added.

  Parameters

  • stateEvents: MatrixEvent[]

    list of state events to initialise the state with.
  • __namedParameters: IInitialiseStateOptions = {}

  Returns void

  Throws

  Error if an attempt is made to call this after addEvent is called.

insertEvent

• insertEvent(
      event: MatrixEvent,
      insertIndex: number,
      roomState: RoomState,
      addToState: boolean,
  ): void
  Internal

  Insert a new event into the timeline, and update the state.

  TEMPORARY: until we have recursive relations, we need this function to exist to allow us to insert events in timeline order, which is our best guess for Sync Order. This is a copy of addEvent above, modified to allow inserting an event at a specific index.

  Parameters

  • event: MatrixEvent
  • insertIndex: number
  • roomState: RoomState
  • addToState: boolean

  Returns void

removeEvent

• removeEvent(eventId: string): null | MatrixEvent

  Remove an event from the timeline

  Parameters

  • eventId: string

    ID of event to be removed

  Returns null | MatrixEvent

  removed event, or null if not found

setNeighbouringTimeline

• setNeighbouringTimeline(neighbour: EventTimeline, direction: Direction): void

  Set the next timeline in the series

  Parameters

  • neighbour: EventTimeline

    previous/following timeline
  • direction: Direction

    EventTimeline.BACKWARDS to set the previous timeline; EventTimeline.FORWARDS to set the next timeline.

  Returns void

  Throws

  Error if an attempt is made to set the neighbouring timeline when it is already set.

setPaginationToken

• setPaginationToken(token: null | string, direction: Direction): void

  Set a pagination token

  Parameters

  • token: null | string

    pagination token
  • direction: Direction

    EventTimeline.BACKWARDS to set the pagination token for going backwards in time; EventTimeline.FORWARDS to set the pagination token for going forwards in time.

  Returns void

toString

• toString(): string

  Return a string to identify this timeline, for debugging

  Returns string

  name for this timeline

StaticsetEventMetadata

• setEventMetadata(
      event: MatrixEvent,
      stateContext: RoomState,
      toStartOfTimeline: boolean,
  ): void

  Static helper method to set sender and target properties

  Parameters

  • event: MatrixEvent

    the event whose metadata is to be set
  • stateContext: RoomState

    the room state to be queried
  • toStartOfTimeline: boolean

    if true the event's forwardLooking flag is set false

  Returns void