Key them off of `onStop()` and `onStart()` which seems to match the
other backends most closely. These [Android Activity lifecycle] events
denote when the application is visible on-screen, and recommend that any
heavy lifting for startup and shutdown happens here, as the application
may be demoted to the background and later shut down entirely unless the
user navigates back to it.
[Android Activity lifecycle]: https://developer.android.com/guide/components/activities/activity-lifecycle
Let the users wake up the event loop and then they could poll their
user sources.
Co-authored-by: Mads Marquart <mads@marquart.dk>
Co-authored-by: daxpedda <daxpedda@gmail.com>
Add a simple `ApplicationHandler` trait since winit is moving towards
trait based API. Add `run_app` group of APIs to accept `&mut impl
ApplicationHandler` deprecating the old `run` APIs.
Part-of: https://github.com/rust-windowing/winit/issues/3432
