Spawning Futures

The use_resource and use_coroutine hooks are useful if you want to unconditionally spawn the future. Sometimes, though, you'll want to only spawn a future in response to an event, such as a mouse click. For example, suppose you need to send a request when the user clicks a "log in" button. For this, you can use spawn:

let mut response = use_signal(|| String::from("..."));

let log_in = move |_| {
    spawn(async move {
        let resp = reqwest::Client::new()
            .get("https://dioxuslabs.com")
            .send()
            .await;

        match resp {
            Ok(_data) => {
                log::info!("dioxuslabs.com responded!");
                response.set("dioxuslabs.com responded!".into());
            }
            Err(err) => {
                log::info!("Request failed with error: {err:?}")
            }
        }
    });
};

rsx! {
    button { onclick: log_in, "Response: {response}" }
}

Note: spawn will always spawn a new future. You most likely don't want to call it on every render.

Calling spawn will give you a JoinHandle which lets you cancel or pause the future.

Spawning Tokio Tasks

Sometimes, you might want to spawn a background task that needs multiple threads or talk to hardware that might block your app code. In these cases, we can directly spawn a Tokio task from our future. For Dioxus-Desktop, your task will be spawned onto Tokio's Multithreaded runtime:

spawn(async {
    let _ = tokio::spawn(async {}).await;

    let _ = tokio::task::spawn_local(async {
        // some !Send work
    })
    .await;
});