Some events not firing

[jquesada2016]

Given the following code:

use leptos::*;
use wasm_bindgen::prelude::*;

#[wasm_bindgen(start)]
pub fn start() {
  mount_to_body(view_fn);
}

fn view_fn(cx: Scope) -> impl Mountable {
  let (focus, set_focus) = create_signal(cx, false);

  let focused = move || {
    if focus() {
      view! { cx, <p></p> }
    } else {
      view! { cx, <span /> }
    }
  };

  view! { cx,
    <div>
      <input on:focus=move |_| set_focus(true) on:blur=move |_| set_focus(false) />
      {focused}
    </div>
  }
}

on:focus and on:blur never fire. on:click does, however.

[gbj]

Oh interesting. Yeah this is because I'm using event delegation, but focus/blur don't bubble.

I guess add_event_listener (or the view macro) needs to check whether an event is in a set of "non-bubbling" events and use a normal event listener rather than event delegation.

https://github.com/gbj/leptos/blob/b9ca0b11a2d8846a83af6a8f37af3dde23c16179/leptos_dom/src/operations.rs#L230-L239

[jquesada2016]

Thankfully, we're in luck. here's a list of all of them. One think to keep in mind however, and those are custom events, what should one do if someone creates a custom event which does not bubble? Should there be a special syntax for this?

[gbj]

See #56. I did test this with a quick input example using focus and blur and the events fire.

I'm open to suggestions for an alternate syntax for custom events which don't bubble. This is tricky because technically it's only known whether any given event bubbles at runtime (by checking its bubbles property or whatever) but by that point it's too late (because you're catching the event within a handler that's either been delegated or not.)

Fortunately erring on the side of caution here is not a big deal, as it's a small deoptimization in any case.