Fix for https://github.com/vector-im/riot-web/issues/4224
Due to the way `MatrixChat` does a state update when the `view_room` dispatch fires and a second update when `RoomViewStore` sends an update, the current event ID and room ID were becoming out of sync. The solution devised was to have the event ID managed by the `RoomViewStore` itself and do any defaulting there (for when we revisit a room that we saved scroll state for previously).
This required a few changes:
- The addition of `update_scroll_state` in `RoomViewStore` allows the `RoomView` to save scroll state for a room before swapping to another one. Previously the caching of scroll state was done in `RoomView`.
- The `view_room` dispatch now accepts an `event_id`, which dictates which event is supposed to be scrolled to in the `MessagePanel` when a new room is viewed. It also accepts `event_offset`, but currently, this isn't passed in by a dispatch in the app, but it is clobbered when loading the default position when an `event_id` isn't specified. Finally, `highlighted` was added to distinguish whether the initial event being scrolled to is also highlighted. This flag is also used by `viewRoom` in `MatrixChat` in order to decide whether to `notifyNewScreen` with the specified `event_id`.
Dispatch so we can set the state in RoomViewStore. Show the error
when the room join fails (unsure if it's better to do this from
the component or the store). Remove unused joinError from roomview.
This allows for the alias resolution to occur before a join is attempted. In theory, join_room could in future do an optional view_room-esque thing before attemping a join which would be less fragile than dispatching things in the right order.
Also, make sure the store indicates that it is not loading when a room ID has been used - no alias resolution need take place.
This prevents RoomView from doing any peeking whilst the join/registration is in progress, causing weirdness with TimelinePanel getPendingEventList (which throws an error if called when peeking).
This allows for a truely flux-y way of storing the currently viewed room, making some callbacks (like onRoomIdResolved) redundant and making sure that the currently viewed room (ID) is only stored in one place as opposed to the previous many places.
This was required for the `join_room` action which can be dispatched to join the currently viewed room.
Another change was to introduce `LifeCycleStore` which is a start at encorporating state related to the lifecycle of the app into a flux store. Currently it only contains an action which will be dispatched when the sync state has become PREPARED. This was necessary to do a deferred dispatch of `join_room` following the registration of a PWLU (PassWord-Less User).
The following actions are introduced:
- RoomViewStore:
- `view_room`: dispatch to change the currently viewed room ID
- `join_room`: dispatch to join the currently viewed room
- LifecycleStore:
- `do_after_sync_prepared`: dispatch to store an action which will be dispatched when `sync_state` is dispatched with `state = 'PREPARED'`
- MatrixChat:
- `sync_state`: dispatched when the sync state changes. Ideally there'd be a SyncStateStore that emitted an `update` upon receiving this, but for now the `LifecycleStore` will listen for `sync_state` directly.
Luke Barnard