leptos_use

Function use_throttle_fn

Source 
pub fn use_throttle_fn<F, R>(
    func: F,
    ms: impl Into<MaybeSignal<f64>> + 'static,
) -> impl Fn() -> Rc<RefCell<Option<R>>> + Clone
where
    F: Fn() -> R + Clone + 'static,
    R: 'static,
Expand description

Throttle execution of a function. Especially useful for rate limiting execution of handlers on events like resize and scroll.

Throttle is a spring that throws balls: After a ball flies out it needs some time to shrink back, so it cannot throw any more balls until it’s ready.

§Demo

Link to Demo

§Usage

let mut throttled_fn = use_throttle_fn(
    || {
        // do something, it will be called at most 1 time per second
    },
    1000.0,
);
view! {
    <button on:click=move |_| { throttled_fn(); }>
        "Smash me!"
    </button>
}

Please note that if the current component is cleaned up before the throttled callback is called, the throttled callback will not be called.

You can provide options when you use use_throttle_fn_with_options.

let throttled_fn = use_throttle_fn_with_options(
    || {
        // do something, it will be called at most 1 time per second
    },
    1000.0,
    ThrottleOptions::default()
        .leading(true)
        .trailing(true),
);

If you want to throttle a function that takes an argument there are also the versions use_throttle_fn_with_arg and use_throttle_fn_with_arg_and_options.

§Server-Side Rendering

Internally this uses setTimeout which is not supported on the server. So usually calling a throttled function on the server will simply be ignored.