DittoAttachmentFetchEvent

The different events that can occur in relation to an attachment fetch.

There are three different attachment fetch events: Completed, Progress, or Deleted.

There will be at most one Completed or Deleted event per attachment fetch. There can be many Progress events delivered for each attachment fetch.

Updates relating to an attachment fetch are delivered by registering a DittoAttachmentFetcher through a call to fetchAttachment on a DittoCollection instance.