# Objective
- Upgrade winit to v0.30
- Fixes https://github.com/bevyengine/bevy/issues/13331
## Solution
This is a rewrite/adaptation of the new trait system described and
implemented in `winit` v0.30.
## Migration Guide
The custom UserEvent is now renamed as WakeUp, used to wake up the loop
if anything happens outside the app (a new
[custom_user_event](https://github.com/bevyengine/bevy/pull/13366/files#diff-2de8c0a8d3028d0059a3d80ae31b2bbc1cde2595ce2d317ea378fe3e0cf6ef2d)
shows this behavior.
The internal `UpdateState` has been removed and replaced internally by
the AppLifecycle. When changed, the AppLifecycle is sent as an event.
The `UpdateMode` now accepts only two values: `Continuous` and
`Reactive`, but the latter exposes 3 new properties to enable reactive
to device, user or window events. The previous `UpdateMode::Reactive` is
now equivalent to `UpdateMode::reactive()`, while
`UpdateMode::ReactiveLowPower` to `UpdateMode::reactive_low_power()`.
The `ApplicationLifecycle` has been renamed as `AppLifecycle`, and now
contains the possible values of the application state inside the event
loop:
* `Idle`: the loop has not started yet
* `Running` (previously called `Started`): the loop is running
* `WillSuspend`: the loop is going to be suspended
* `Suspended`: the loop is suspended
* `WillResume`: the loop is going to be resumed
Note: the `Resumed` state has been removed since the resumed app is just
running.
Finally, now that `winit` enables this, it extends the `WinitPlugin` to
support custom events.
## Test platforms
- [x] Windows
- [x] MacOs
- [x] Linux (x11)
- [x] Linux (Wayland)
- [x] Android
- [x] iOS
- [x] WASM/WebGPU
- [x] WASM/WebGL2
## Outstanding issues / regressions
- [ ] iOS: build failed in CI
- blocking, but may just be flakiness
- [x] Cross-platform: when the window is maximised, changes in the scale
factor don't apply, to make them apply one has to make the window
smaller again. (Re-maximising keeps the updated scale factor)
- non-blocking, but good to fix
- [ ] Android: it's pretty easy to quickly open and close the app and
then the music keeps playing when suspended.
- non-blocking but worrying
- [ ] Web: the application will hang when switching tabs
- Not new, duplicate of https://github.com/bevyengine/bevy/issues/13486
- [ ] Cross-platform?: Screenshot failure, `ERROR present_frames:
wgpu_core::present: No work has been submitted for this frame before`
taking the first screenshot, but after pressing space
- non-blocking, but good to fix
---------
Co-authored-by: François <francois.mockers@vleue.com>
