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use web_sys::Element;
use yew::prelude::*;
use super::{use_event, use_mount};
/// A sensor hook that tracks an HTML element's scroll position.
///
/// # Example
///
/// ```rust
/// # use yew::prelude::*;
/// #
/// use yew_hooks::prelude::*;
///
/// #[function_component(UseScroll)]
/// fn scroll() -> Html {
/// let node = use_node_ref();
/// let state = use_scroll(node.clone());
///
/// html! {
/// <div ref={node}>
/// <b>{ " X: " }</b>
/// { state.0 }
/// <b>{ " Y: " }</b>
/// { state.1 }
/// </div>
/// }
/// }
/// ```
#[hook]
pub fn use_scroll(node: NodeRef) -> (i32, i32) {
let state = use_state(|| (0, 0));
{
let state = state.clone();
let node = node.clone();
use_event(node, "scroll", move |e: Event| {
let element: Element = e.target_unchecked_into();
#[allow(clippy::unnecessary_cast)]
state.set((element.scroll_left() as i32, element.scroll_top() as i32));
});
}
{
let state = state.clone();
use_mount(move || {
if let Some(element) = node.cast::<Element>() {
#[allow(clippy::unnecessary_cast)]
state.set((element.scroll_left() as i32, element.scroll_top() as i32));
}
});
}
*state
}