* Stop sharing state observables when the view model is destroyed
By default, observables running with shareReplay will continue running forever even if there are no subscribers. We need to stop them when the view model is destroyed to avoid memory leaks and other unintuitive behavior.
* Hydrate the call view model in a less hacky way
This ensures that only a single view model is created per call, unlike the previous solution which would create extra view models in strict mode which it was unable to dispose of. The other way was invalid because React gives us no way to reliably dispose of a resource created in the render phase. This is essentially a memory leak fix.
* Add simple global controls to put the call in picture-in-picture mode
Our web and mobile apps (will) all support putting calls into a picture-in-picture mode. However, it'd be nice to have a way of doing this that's more explicit than a breakpoint, because PiP views could in theory get fairly large. Specifically, on mobile, we want a way to do this that can tell you whether the call is ongoing, and that works even without the widget API (because we support SPA calls in the Element X apps…)
To this end, I've created a simple global "controls" API on the window. Right now it only has methods for controlling the picture-in-picture state, but in theory we can expand it to also control mute states, which is current possible via the widget API only.
* Fix footer appearing in large PiP views
* Add a method for whether you can enter picture-in-picture mode
* Have the controls emit booleans directly
react-rxjs is the library we've been using to connect our React components to view models and consume observables. However, after spending some time with react-rxjs, I feel that it's a very heavy-handed solution. It requires us to sprinkle <Subscribe /> and <RemoveSubscribe /> components all throughout the code, and makes React go through an extra render cycle whenever we mount a component that binds to a view model. What I really want is a lightweight React hook that just gets the current value out of a plain observable, without any extra setup. Luckily the observable-hooks library with its useObservableEagerState hook seems to do just that—and it's more actively maintained, too!
Here I've implemented an MVP for the new unified grid layout, which scales smoothly up to arbitrarily many participants. It doesn't yet have a special 1:1 layout, so in spotlight mode and 1:1s, we will still fall back to the legacy grid systems.
Things that happened along the way:
- The part of VideoTile that is common to both spotlight and grid tiles, I refactored into MediaView
- VideoTile renamed to GridTile
- Added SpotlightTile for the new, glassy spotlight designs
- NewVideoGrid renamed to Grid, and refactored to be even more generic
- I extracted the media name logic into a custom React hook
- Deleted the BigGrid experiment
This is a start at implementing the call layouts from the new designs. I've added data types to model the contents of each possible layout, and begun implementing the business logic to produce these layouts in the call view model.