Add WASM CustomEvent Example #2852
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@rukai I guess I didn't really think my last comment through (#2816 (comment)) , but you can't really show the JS in the generated HTML file because it's inserted during runtime, or is there something cargo-run-wasm can do about that I'm not aware of?
Additionally, it would also be really nice to not have to build a bunch of HTML through JS or web-sys. Again, none of this can actually be shown to the user because it's all added during runtime.
examples/wasm_custom_event.rs
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| // Because EventLoopProxy is not Send, we need to wrap it in a RefCell and use thread_local! | ||
| thread_local! { | ||
| pub static EVENT_LOOP_PROXY: RefCell<Option<EventLoopProxy<CustomEvent>>> = RefCell::new(None); | ||
| } |
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Since #2834 it is actually!
In any case it's still appropriate to use thread_local! if we aren't doing anything with web workers.
We should also probably use once_cell::unsync::OnceCell instead of RefCell.
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I am not certain want to make the comment now. Not super familiar with web workers. (js is single threaded unless you use web-workers is my understanding (?))
| // Function to be called from JS | ||
| fn wasm_call() -> u32 { | ||
| 42 | ||
| } | ||
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| #[derive(Debug, Clone, Copy)] | ||
| pub enum CustomEvent { | ||
| WasmCall, | ||
| } |
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Let's make a slightly more useful example. Instead of just printing 42 we could e.g. use Window::set_inner_size(), which is a valid use-case and would also show how to pass parameters. This would require two input fields for width and height and a button to send.
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Awaiting if the cargo-wasm-runner will go through first. rukai/cargo-run-wasm#36
| Event::WindowEvent { | ||
| event: WindowEvent::CloseRequested, | ||
| window_id, | ||
| } if window_id == window.id() => control_flow.set_exit(), |
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We can skip that here, it's not a thing in Wasm.
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Skip this match arm?
Event::WindowEvent {
event: WindowEvent::CloseRequested,
window_id,
} if window_id == window.id() => control_flow.set_exit(),
Oh uh... true. 😅 Next best thing I can think of would be just manually creating an unused html file with the appropriate javascript in it :/ |
Would you accept a feature request extending the API of |
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Yep, I think we do need this feature, I've raised rukai/cargo-run-wasm#35 |
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I could consider looking into adding that feature. Looks relatively straightforward via web_sys |
Co-authored-by: daxpedda <[email protected]>
Co-authored-by: daxpedda <[email protected]>
…venhuyn/winit into stevenhuyn/wasm-custom-event
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@stevenhuyn you should keep the conversation you are having in #2816 (comment) here! |
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Ah thought the issue is the ground truth, although I guess implementation details should be in this PR (?) I have hooked it up to test (pointing cargo run wasm crate to my fork) and have it all working. Need to look into why CI failing, cause it builds perfectly fine on my machine. |
The current CustomEvent example in the ./examples folder doesn't show how to do it via WASM.
Atm I'm just printing to console, however we could reuse the
examples/web.rscode to append to a HTML list. But I wanted to keep the example a bit more streamline.Also I added some extra CSS to centre align it. The button will be placed on the right of the canvas otherwise. lmk if it's uggo and I'll revert it.
Closes #2816
Answers #2061 (comment)
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