Function leptos_use::use_event_listener

pub fn use_event_listener<Ev, El, T, F>(
    target: El,
    event: Ev,
    handler: F,
) -> impl Fn() + Clone
where
    Ev: EventDescriptor + 'static,
    El: Into<ElementMaybeSignal<T, EventTarget>>,
    T: Into<EventTarget> + Clone + 'static,
    F: FnMut(<Ev as EventDescriptor>::EventType) + 'static,

Use EventListener with ease. Register using addEventListener on mounted, and removeEventListener automatically on cleanup.

Usage

use_event_listener(use_document(), visibilitychange, |evt| {
    log!("{:?}", evt);
});

You can also pass a NodeRef as the event target, use_event_listener will unregister the previous event and register the new one when you change the target.

let element = create_node_ref();

use_event_listener(element, click, |evt| {
    log!("click from element {:?}", event_target::<web_sys::HtmlDivElement>(&evt));
});

let (cond, set_cond) = create_signal(true);

view! {
    <Show
        when=move || cond.get()
        fallback=move || view! { <div node_ref=element>"Condition false"</div> }
    >
        <div node_ref=element>"Condition true"</div>
    </Show>
}

You can also call the returned to unregister the listener.

let cleanup = use_event_listener(document().body(), keydown, |evt: KeyboardEvent| {
    log!("{}", &evt.key());
});

cleanup();

Server-Side Rendering

On the server this amounts to a noop.