leptos_use/
use_element_hover.rs

1use crate::core::IntoElementMaybeSignal;
2use crate::{use_event_listener_with_options, UseEventListenerOptions};
3use default_struct_builder::DefaultBuilder;
4use leptos::ev::{mouseenter, mouseleave};
5use leptos::leptos_dom::helpers::TimeoutHandle;
6use leptos::prelude::*;
7use leptos::reactive::wrappers::read::Signal;
8
9/// Reactive element's hover state.
10///
11/// ## Demo
12///
13/// [Link to Demo](https://github.com/Synphonyte/leptos-use/tree/main/examples/use_element_hover)
14///
15/// ## Usage
16///
17/// ```
18/// # use leptos::prelude::*;
19/// # use leptos::html::Button;
20/// # use leptos_use::use_element_hover;
21/// #
22/// # #[component]
23/// # fn Demo() -> impl IntoView {
24/// let el = NodeRef::<Button>::new();
25/// let is_hovered = use_element_hover(el);
26///
27/// view! {
28///     <button node_ref=el>{ move || format!("{:?}", is_hovered.get()) }</button>
29/// }
30/// # }
31/// ```
32///
33/// ## Server-Side Rendering
34///
35/// On the server this returns a `Signal` that always contains the value `false`.
36pub fn use_element_hover<El, M>(el: El) -> Signal<bool>
37where
38    El: IntoElementMaybeSignal<web_sys::EventTarget, M>,
39{
40    use_element_hover_with_options(el, UseElementHoverOptions::default())
41}
42
43/// Version of [`use_element_hover`] that takes a `UseElementHoverOptions`. See [`use_element_hover`] for how to use.
44
45#[cfg_attr(feature = "ssr", allow(unused_variables, unused_mut))]
46pub fn use_element_hover_with_options<El, M>(
47    el: El,
48    options: UseElementHoverOptions,
49) -> Signal<bool>
50where
51    El: IntoElementMaybeSignal<web_sys::EventTarget, M>,
52{
53    let UseElementHoverOptions {
54        delay_enter,
55        delay_leave,
56    } = options;
57
58    let (is_hovered, set_hovered) = signal(false);
59
60    let timer = StoredValue::new(None::<TimeoutHandle>);
61
62    let toggle = move |entering: bool| {
63        #[cfg(not(feature = "ssr"))]
64        {
65            let delay = if entering { delay_enter } else { delay_leave };
66
67            timer.update_value(|timer| {
68                if let Some(handle) = timer.take() {
69                    handle.clear();
70                }
71            });
72
73            if delay > 0 {
74                timer.set_value(
75                    set_timeout_with_handle(
76                        move || set_hovered.set(entering),
77                        std::time::Duration::from_millis(delay),
78                    )
79                    .ok(),
80                );
81            } else {
82                set_hovered.set(entering);
83            }
84        }
85    };
86
87    let listener_options = UseEventListenerOptions::default().passive(true);
88
89    let el = el.into_element_maybe_signal();
90
91    let _ =
92        use_event_listener_with_options(el, mouseenter, move |_| toggle(true), listener_options);
93
94    let _ =
95        use_event_listener_with_options(el, mouseleave, move |_| toggle(false), listener_options);
96
97    is_hovered.into()
98}
99
100/// Options for [`use_element_hover_with_options`].
101#[derive(DefaultBuilder, Default)]
102pub struct UseElementHoverOptions {
103    /// The time in ms the mouse has to be hovered over the element before the signal is changed to `true`. Defaults to `0`.
104    delay_enter: u64,
105
106    /// The time in ms after the mouse has left the element before the signal is changed to `false`. Defaults to `0`.
107    delay_leave: u64,
108}
leptos_use/use_element_hover.rs

leptos_use/
use_element_hover.rs
