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                <ol class="chapter"><li class="chapter-item expanded affix "><a href="../index.html">Introdução</a></li><li class="chapter-item expanded "><a href="../getting_started/index.html"><strong aria-hidden="true">1.</strong> Introdução Rápida as Plataformas</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../getting_started/desktop.html"><strong aria-hidden="true">1.1.</strong> Desktop</a></li><li class="chapter-item expanded "><a href="../getting_started/web.html"><strong aria-hidden="true">1.2.</strong> Web</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../getting_started/hot_reload.html"><strong aria-hidden="true">1.2.1.</strong> Hot Reload</a></li></ol></li><li class="chapter-item expanded "><a href="../getting_started/ssr.html"><strong aria-hidden="true">1.3.</strong> Renderização por Servidor</a></li><li class="chapter-item expanded "><a href="../getting_started/tui.html"><strong aria-hidden="true">1.4.</strong> Interface do Terminal</a></li><li class="chapter-item expanded "><a href="../getting_started/mobile.html"><strong aria-hidden="true">1.5.</strong> Móvel</a></li></ol></li><li class="chapter-item expanded "><a href="../describing_ui/index.html"><strong aria-hidden="true">2.</strong> Descrevendo a Interface do Usuário</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../describing_ui/special_attributes.html"><strong aria-hidden="true">2.1.</strong> Atributos Especiais</a></li><li class="chapter-item expanded "><a href="../describing_ui/components.html"><strong aria-hidden="true">2.2.</strong> Componentes</a></li><li class="chapter-item expanded "><a href="../describing_ui/component_props.html"><strong aria-hidden="true">2.3.</strong> Props</a></li><li class="chapter-item expanded "><a href="../describing_ui/component_children.html"><strong aria-hidden="true">2.4.</strong> Componente Filho</a></li></ol></li><li class="chapter-item expanded "><a href="../interactivity/index.html"><strong aria-hidden="true">3.</strong> Interatividade</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../interactivity/event_handlers.html"><strong aria-hidden="true">3.1.</strong> Manipuladores de Eventos</a></li><li class="chapter-item expanded "><a href="../interactivity/hooks.html"><strong aria-hidden="true">3.2.</strong> Hooks &amp; Estado de Componentes</a></li><li class="chapter-item expanded "><a href="../interactivity/user_input.html"><strong aria-hidden="true">3.3.</strong> Entradas do Usuário</a></li><li class="chapter-item expanded "><a href="../interactivity/sharing_state.html"><strong aria-hidden="true">3.4.</strong> Estado Compartilhado</a></li><li class="chapter-item expanded "><a href="../interactivity/custom_hooks.html"><strong aria-hidden="true">3.5.</strong> Hooks Personalizados</a></li><li class="chapter-item expanded "><a href="../interactivity/dynamic_rendering.html"><strong aria-hidden="true">3.6.</strong> Renderização Dinâmica</a></li><li class="chapter-item expanded "><a href="../interactivity/roteador.html"><strong aria-hidden="true">3.7.</strong> Roteamento</a></li></ol></li><li class="chapter-item expanded "><a href="../async/index.html"><strong aria-hidden="true">4.</strong> Assincronia</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../async/use_future.html"><strong aria-hidden="true">4.1.</strong> UseFuture</a></li><li class="chapter-item expanded "><a href="../async/use_coroutine.html"><strong aria-hidden="true">4.2.</strong> UseCoroutine</a></li><li class="chapter-item expanded "><a href="../async/spawn.html"><strong aria-hidden="true">4.3.</strong> Gerando Futures</a></li></ol></li><li class="chapter-item expanded "><a href="../best_practices/index.html"><strong aria-hidden="true">5.</strong> Práticas Recomendadas</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../best_practices/error_handling.html"><strong aria-hidden="true">5.1.</strong> Tratamento de erros</a></li><li class="chapter-item expanded "><a href="../best_practices/antipatterns.html" class="active"><strong aria-hidden="true">5.2.</strong> Antipadrões</a></li></ol></li><li class="chapter-item expanded "><a href="../publishing/index.html"><strong aria-hidden="true">6.</strong> Publicação</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../publishing/desktop.html"><strong aria-hidden="true">6.1.</strong> Desktop</a></li><li class="chapter-item expanded "><a href="../publishing/web.html"><strong aria-hidden="true">6.2.</strong> Web</a></li><li class="spacer"></li></ol></li><li class="chapter-item expanded "><a href="../custom_renderer/index.html"><strong aria-hidden="true">7.</strong> Renderizador Personalizado</a></li><li class="spacer"></li><li class="chapter-item expanded affix "><a href="../roadmap.html">Roteiro</a></li><li class="chapter-item expanded affix "><a href="../contributing.html">Contribuindo</a></li></ol>
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                        <h1 id="antipadrões"><a class="header" href="#antipadrões">Antipadrões</a></h1>
<p>Este exemplo mostra o que não fazer e fornece uma razão pela qual um determinado padrão é considerado um &quot;AntiPattern&quot;. A maioria dos antipadrões são considerados errados por motivos de desempenho ou por prejudicar a reutilização do código.</p>
<h2 id="fragmentos-aninhados-desnecessariamente"><a class="header" href="#fragmentos-aninhados-desnecessariamente">Fragmentos Aninhados Desnecessariamente</a></h2>
<p>Os fragmentos não montam um elemento físico no DOM imediatamente, então o Dioxus deve recorrer a seus filhos para encontrar um nó DOM físico. Este processo é chamado de &quot;normalização&quot;. Isso significa que fragmentos profundamente aninhados fazem o Dioxus realizar um trabalho desnecessário. Prefira um ou dois níveis de fragmentos/componentes aninhados até apresentar um elemento DOM verdadeiro.</p>
<p>Apenas os nós Componente e Fragmento são suscetíveis a esse problema. O Dioxus atenua isso com componentes fornecendo uma API para registrar o estado compartilhado sem o padrão <em>Context Provider</em>.</p>
<pre><pre class="playground"><code class="language-rust edition2018">
<span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>    // ❌ Don't unnecessarily nest fragments
    let _ = cx.render(rsx!(
        Fragment {
            Fragment {
                Fragment {
                    Fragment {
                        Fragment {
                            div { &quot;Finally have a real node!&quot; }
                        }
                    }
                }
            }
        }
    ));

    // ✅ Render shallow structures
    cx.render(rsx!(
        div { &quot;Finally have a real node!&quot; }
    ))
<span class="boring">}
</span></code></pre></pre>
<h2 id="chaves-do-iterador-incorretas"><a class="header" href="#chaves-do-iterador-incorretas">Chaves do Iterador Incorretas</a></h2>
<p>Conforme descrito no capítulo de renderização condicional, os itens da lista devem ter <em>keys</em> exclusivas associadas aos mesmos itens nas renderizações. Isso ajuda o Dioxus a associar o estado aos componentes contidos e garante um bom desempenho de diferenciação. Não omita as <em>keys</em>, a menos que você saiba que a lista é estática e nunca será alterada.</p>
<pre><pre class="playground"><code class="language-rust edition2018">
<span class="boring">#![allow(unused)]
</span><span class="boring">fn main() {
</span>    let data: &amp;HashMap&lt;_, _&gt; = &amp;cx.props.data;

    // ❌ No keys
    cx.render(rsx! {
        ul {
            data.values().map(|value| rsx!(
                li { &quot;List item: {value}&quot; }
            ))
        }
    });

    // ❌ Using index as keys
    cx.render(rsx! {
        ul {
            cx.props.data.values().enumerate().map(|(index, value)| rsx!(
                li { key: &quot;{index}&quot;, &quot;List item: {value}&quot; }
            ))
        }
    });

    // ✅ Using unique IDs as keys:
    cx.render(rsx! {
        ul {
            cx.props.data.iter().map(|(key, value)| rsx!(
                li { key: &quot;{key}&quot;, &quot;List item: {value}&quot; }
            ))
        }
    })
<span class="boring">}
</span></code></pre></pre>
<h2 id="evite-mutabilidade-interior-em-props"><a class="header" href="#evite-mutabilidade-interior-em-props">Evite Mutabilidade Interior em <code>Props</code></a></h2>
<p>Embora seja tecnicamente aceitável ter um <code>Mutex</code> ou um <code>RwLock</code> nos <em>props</em>, eles serão difíceis de usar.</p>
<p>Suponha que você tenha um <em>struct</em> <code>User</code> contendo o campo <code>username: String</code>. Se você passar uma <em>prop</em> <code>Mutex&lt;User&gt;</code> para um componente <code>UserComponent</code>, esse componente pode querer passar o nome de usuário como uma <em>prop</em> <code>&amp;str</code> para um componente filho. No entanto, ele não pode passar esse campo emprestado, pois ele só viveria enquanto o bloqueio do <code>Mutex</code>, que pertence à função <code>UserComponent</code>. Portanto, o componente será forçado a clonar o campo <code>username</code>.</p>
<h2 id="evite-atualizar-o-estado-durante-a-renderização"><a class="header" href="#evite-atualizar-o-estado-durante-a-renderização">Evite Atualizar o Estado Durante a Renderização</a></h2>
<p>Toda vez que você atualiza o estado, o Dioxus precisa renderizar novamente o componente – isso é ineficiente! Considere refatorar seu código para evitar isso.</p>
<p>Além disso, se você atualizar incondicionalmente o estado durante a renderização, ele será renderizado novamente em um <em>loop</em> infinito.</p>

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