Calling the `Drop` impl of the user's `ApplicationHandler` is important on
iOS and Web, since they don't return from `EventLoop::run_app`.
And now that we reliably call `Drop`, the `ApplicationHandler::exited`
event/callback is unnecessary; using `Drop` composes much better (open files
etc. stored in the app state will be automatically flushed), and prevents
weirdness like attempting to create a new window while exiting.
Due to casts and use of platform specific crates in those modules
it's not really feasible to build docs for them.
After separating crates, thus should become way easier to navigate,
since backends information would be publicly available.
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
