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                        <h1 id="spawning-futures"><a class="header" href="#spawning-futures">Spawning Futures</a></h1>
<p>The <code>use_future</code> and <code>use_coroutine</code> 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 &quot;log in&quot; button. For this, you can use <code>cx.spawn</code>:</p>
<pre><pre class="playground"><code class="language-rust edition2018">
<span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>    let logged_in = use_state(cx, || false);

    let log_in = move |_| {
        cx.spawn({
            let logged_in = logged_in.to_owned();

            async move {
                let resp = reqwest::Client::new()
                    .post(&quot;http://example.com/login&quot;)
                    .send()
                    .await;

                match resp {
                    Ok(_data) =&gt; {
                        println!(&quot;Login successful!&quot;);
                        logged_in.set(true);
                    }
                    Err(_err) =&gt; {
                        println!(
                            &quot;Login failed - you need a login server running on localhost:8080.&quot;
                        )
                    }
                }
            }
        });
    };

    cx.render(rsx! {
        button {
            onclick: log_in,
            &quot;Login&quot;,
        }
    })
<span class="boring">}
</span></code></pre></pre>
<blockquote>
<p>Note: <code>spawn</code> will always spawn a <em>new</em> future. You most likely don't want to call it on every render.</p>
</blockquote>
<p>Calling <code>spawn</code> will give you a <code>JoinHandle</code> which lets you cancel or pause the future.</p>
<h2 id="spawning-tokio-tasks"><a class="header" href="#spawning-tokio-tasks">Spawning Tokio Tasks</a></h2>
<p>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:</p>
<pre><pre class="playground"><code class="language-rust edition2018">
<span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>        cx.spawn(async {
            let _ = tokio::spawn(async {}).await;

            let _ = tokio::task::spawn_local(async {
                // some !Send work
            })
            .await;
        });
<span class="boring">}
</span></code></pre></pre>

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