watch_with_options
A version of leptos::watch but with additional options.
Immediate
This is the same as for leptos::watch. But you don’t have to specify it.
By default its set to false.
If immediate is true, the callback will run immediately (this is also true if throttled/debounced).
If it’s false, the callback will run only after
the first change is detected of any signal that is accessed in deps.
use leptos::prelude::*;
use leptos::logging::log;
use leptos_use_watch_with_options::{watch_with_options, WatchOptions};
pub fn Demo() -> impl IntoView {
let (num, set_num) = signal(0);
watch_with_options(
move || num.get(),
move |num, _, _| {
log!("Number {}", num);
},
WatchOptions::default().immediate(true),
); // > "Number 0"
set_num.set(1); // > "Number 1"
view! { }
}Filters
The callback can be throttled or debounced. Please see watch_throttled
and watch_debounced for details.
use leptos::prelude::*;
use leptos::logging::log;
use leptos_use_watch_with_options::{watch_with_options, WatchOptions};
pub fn Demo() -> impl IntoView {
let (num, set_num) = signal(0);
watch_with_options(
move || num.get(),
move |num, _, _| {
log!("Number {}", num);
},
WatchOptions::default().throttle(100.0), // there's also `throttle_with_options`
);
view! { }
}use leptos::prelude::*;
use leptos::logging::log;
use leptos_use_watch_with_options::{watch_with_options, WatchOptions};
pub fn Demo() -> impl IntoView {
let (num, set_num) = signal(0);
watch_with_options(
move || num.get(),
move |num, _, _| {
log!("number {}", num);
},
WatchOptions::default().debounce(100.0), // there's also `debounce_with_options`
);
view! { }
}Server-Side Rendering
Make sure you follow the instructions in Server-Side Rendering.
On the server this works just fine except if you throttle or debounce in which case the callback
will never be called except if you set immediate to true in which case the callback will be
called exactly once when watch() is executed.
See also
Installation
cargo add leptos-use-watch-with-options
Options
WatchOptions
Options for watch_with_options
The filter is a type parameter so that the debounce and throttle code is only compiled into your app if you use it.
Every option is set with a builder method of the same name, e.g. WatchOptions::default().immediate(...). See also the API docs.
immediate
Type: bool
If immediate is true, the callback will run immediately.
If it’s false, the callbackwill run only after the first change is detected of any signal that is accessed indeps. Defaults to false`.
filter
Type: F
Allows to debounce or throttle the callback with a FilterOptions. Defaults to no filter.