Any good examples of conversions from "run" to "run_app"?

[John-Nagle]

Ref: https://docs.rs/winit/0.30.8/winit/event_loop/struct.EventLoop.html#method.run_app

This looks like a tough conversion. I have to fix about four event loops in different programs, all written by others. This is in an area known for per-platform troubles, and hard to test. Is there any safe way to convert old event loops easily

Is it possible to emulate the old interface?

[John-Nagle]

I've now found and read the redesign at #3367
I wish I'd noticed that was going on before it was too late.

It looks like Winit is being converted from a library to a framework. (Users call a library. A framework calls you. Libraries are subordinates. Frameworks are bosses.) Applications using Winit are supposed to be restructured to look like this:

// User code
struct App {
    window: Option<Window>,
}
impl Application for App { ... }

fn main() {
    event_loop.run(App { window: None })?;
}

That's a huge change. Nowhere did someone come right out and say "Winit is becoming a framework". [This changelog entry ](https://docs.rs/winit/latest/winit/changelog/index.html#deprecated does hint at that, but did not make it clear how drastic a change was being contemplated.

This is a big problem if there's already another framework in place, one that uses Winit as a library. Now we have two event loops, both of which want to be in charge. I'm still using Rend3, which has its own incompatible framework system. If I have to redesign that and everything I have that uses it, I'm looking at a month of wasted effort, at least. Everybody who had another event loop now has a big problem.

Some people were talking about forking Winit at 0.29 to avoid this. Did that happen?

[kchibisov]

How this is different to what we had in 0.29? You simply was passing callback and winit was running and taking all the control, now you pass a state instead of implicit borrowed list, so it's all semantically the same.

With the except of async.