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Normal</a></li><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Floats" class="only-in-en-us">Floats</a></li><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Positioning" class="only-in-en-us">Positioning</a></li><li><a href="/pt-BR/docs/Learn_web_development/Core/CSS_layout/Flexbox">Flexbox</a></li><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Grids" class="only-in-en-us">CSS grid layout</a></li><li><a href="/pt-BR/docs/Learn_web_development/Core/CSS_layout/Responsive_Design">Design Responsivo</a></li><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Media_queries" class="only-in-en-us">Media query fundamentals</a></li><li><a href="/en-US/docs/Learn_web_development/Core/CSS_layout/Fundamental_Layout_Comprehension" class="only-in-en-us">Challenge: Fundamental layout comprehension</a></li></ol></details></li><li class="toggle"><details open=""><summary><a href="/pt-BR/docs/Learn_web_development/Core/Scripting">Dynamic scripting with JavaScript</a></summary><ol><li><a href="/pt-BR/docs/Learn_web_development/Core/Scripting/What_is_JavaScript">O que é JavaScript?</a></li><li><a href="/pt-BR/docs/Learn_web_development/Core/Scripting/A_first_splash">Um primeiro mergulho no JavaScript</a></li><li><a href="/pt-BR/docs/Learn_web_development/Core/Scripting/What_went_wrong">O que deu errado? 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href="/pt-BR/docs/Learn_web_development/Core/Scripting/Network_requests">AJAX</a></li><li><a href="/pt-BR/docs/Learn_web_development/Core/Scripting/JSON">Trabalhando com JSON</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript" class="only-in-en-us">Debugging JavaScript and handling errors</a></li></ol></details></li><li class="toggle"><details><summary><a href="/pt-BR/docs/Learn_web_development/Core/Frameworks_libraries">JavaScript frameworks and libraries</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Core/Frameworks_libraries/Introduction" class="only-in-en-us">Introduction to client-side frameworks</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Frameworks_libraries/Main_features" class="only-in-en-us">Framework main features</a></li><li><a href="/pt-BR/docs/Learn_web_development/Core/Frameworks_libraries/React_getting_started">Começando com React</a></li><li><a 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multimedia</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Accessibility/Mobile" class="only-in-en-us">Mobile accessibility</a></li><li><a href="/pt-BR/docs/Learn_web_development/Core/Accessibility/Accessibility_troubleshooting">Avaliação: solucionando problemas de acessibilidade</a></li></ol></details></li><li><a href="/en-US/docs/Learn_web_development/Core/Design_for_developers" class="only-in-en-us">Design for developers</a></li><li><a href="/en-US/docs/Learn_web_development/Core/Version_control" class="only-in-en-us">Version control</a></li><li class="section"><a href="/en-US/docs/Learn_web_development/Extensions" class="only-in-en-us">Extension modules</a></li><li class="toggle"><details><summary><a href="/pt-BR/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects">Advanced JavaScript objects</a></summary><ol><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes">Protótipos de objetos</a></li><li><a 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href="/en-US/docs/Learn_web_development/Extensions/Async_JS/Implementing_a_promise-based_API" class="only-in-en-us">How to implement a promise-based API</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Async_JS/Introducing_workers" class="only-in-en-us">Introducing workers</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Async_JS/Sequencing_animations" class="only-in-en-us">Challenge: Sequencing animations</a></li></ol></details></li><li class="toggle"><details><summary><a href="/pt-BR/docs/Learn_web_development/Extensions/Forms">Web forms — Working with user data</a></summary><ol><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Forms/Your_first_form">Meu primeiro formulário HTML</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Forms/How_to_structure_a_web_form">Como estruturar um formulário HTML</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/Basic_native_form_controls" class="only-in-en-us">Basic native form controls</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/HTML5_input_types" class="only-in-en-us">The HTML5 input types</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/Other_form_controls" class="only-in-en-us">Other form controls</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/Styling_web_forms" class="only-in-en-us">Styling web forms</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/Advanced_form_styling" class="only-in-en-us">Advanced form styling</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Forms/UI_pseudo-classes" class="only-in-en-us">UI pseudo-classes</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Forms/Form_validation">Form data validation</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Forms/Sending_and_retrieving_form_data">Sending form data</a></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_tools" class="only-in-en-us">Understanding client-side tools</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Overview" class="only-in-en-us">Client-side tooling overview</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Package_management" class="only-in-en-us">Package management basics</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Introducing_complete_toolchain" class="only-in-en-us">Introducing a complete toolchain</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Deployment" class="only-in-en-us">Deploying our app</a></li></ol></details></li><li class="toggle"><details><summary><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side">Server-side websites</a></summary><ol><li class="toggle"><details><summary><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/First_steps">Server-side first steps</a></summary><ol><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/First_steps/Introduction">Introdução ao lado servidor</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/First_steps/Client-Server_overview">Visão geral do cliente-servidor</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Web_frameworks" class="only-in-en-us">Server-side web frameworks</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/First_steps/Website_security">Segurança em aplicação web</a></li></ol></details></li><li class="toggle"><details><summary><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django">Framework Web Django (Python)</a></summary><ol><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Introduction">Introdução ao Django</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/development_environment">Configurando um ambiente de desenvolvimento Django</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Tutorial_local_library_website">Tutorial Django: Website da Biblioteca Local</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/skeleton_website">Django Tutorial Parte 2: Criando o "esqueleto" de um site</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Models">Tutorial Django Parte 3: Usando models</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Admin_site">Tutorial Django Parte 4: Django admin site</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Home_page">Django Tutorial Parte 5: Criando nossa home page</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Generic_views">Tutorial Django Parte 6: Lista genérica e detail views</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Sessions">Tutorial Django Parte 7: Sessões</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Authentication">Tutorial Django Parte 8: Autenticação de usuário e permissões</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Forms">Tutorial Django Parte 9: Trabalhando com formulários</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Testing">Tutorial Django Parte 10: Testando uma aplicação web Django</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Deployment">Tutorial Django Parte 11: Hospedando Django para produção</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/web_application_security">Segurança de aplicações web Django</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Django/django_assessment_blog" class="only-in-en-us">Assessment: DIY Django mini blog</a></li></ol></details></li><li class="toggle"><details><summary><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs">Express web framework (Node.js)</a></summary><ol><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Introduction">Introdução Express/Node</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/development_environment">Configurando o Node como ambiente de desenvolvimento</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Tutorial_local_library_website">Express: Tutorial para criar o site de uma Biblioteca Local</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/skeleton_website">Express Tutorial Parte 2: Criando a estrutura do website</a></li><li><a href="/pt-BR/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/mongoose">Tutorial Express Parte 3: Usando um banco de dados (com Mongoose)</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/routes" class="only-in-en-us">Express Tutorial Part 4: Routes and controllers</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Displaying_data" class="only-in-en-us">Express Tutorial Part 5: Displaying library data</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/forms" class="only-in-en-us">Express Tutorial Part 6: Working with forms</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/deployment" class="only-in-en-us">Express Tutorial Part 7: Deploying to production</a></li></ol></details></li></ol></details></li><li class="toggle"><details><summary><a href="/en-US/docs/Learn_web_development/Extensions/Performance" class="only-in-en-us">Web performance</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/why_web_performance" class="only-in-en-us">The "why" of web performance</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/What_is_web_performance" class="only-in-en-us">What is web performance?</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/Perceived_performance" class="only-in-en-us">Perceived performance</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/Measuring_performance" class="only-in-en-us">Measuring performance</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/Multimedia" class="only-in-en-us">Multimedia: Images</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/video" class="only-in-en-us">Multimedia: video</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/JavaScript" class="only-in-en-us">JavaScript performance optimization</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/HTML" class="only-in-en-us">HTML performance optimization</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/CSS" class="only-in-en-us">CSS performance optimization</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Performance/business_case_for_performance" class="only-in-en-us">The business case for web performance</a></li></ol></details></li><li class="toggle"><details><summary><a href="/pt-BR/docs/Learn_web_development/Extensions/Testing">Testing</a></summary><ol><li><a href="/en-US/docs/Learn_web_development/Extensions/Testing/Introduction" class="only-in-en-us">Introduction to cross-browser testing</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Testing/Testing_strategies" class="only-in-en-us">Strategies for carrying out testing</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Testing/HTML_and_CSS" class="only-in-en-us">Handling common HTML and CSS problems</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Testing/Feature_detection" class="only-in-en-us">Implementing feature detection</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Testing/Automated_testing" class="only-in-en-us">Introduction to automated testing</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Testing/Your_own_automation_environment" class="only-in-en-us">Setting up your own test automation environment</a></li></ol></details></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Transform_animate" class="only-in-en-us">Transform and animate CSS</a></li><li><a href="/en-US/docs/Learn_web_development/Extensions/Security_privacy" class="only-in-en-us">Security and privacy</a></li><li class="section">Mais recursos</li><li class="toggle"><details><summary><a href="/pt-BR/docs/Learn_web_development/Howto">How to solve common problems</a></summary><ol><li><a href="/pt-BR/docs/Learn_web_development/Howto/Solve_HTML_problems">Use HTML para resolver problemas comuns</a></li><li><a href="/en-US/docs/Learn_web_development/Howto/Solve_CSS_problems" class="only-in-en-us">Solve common CSS problems</a></li><li><a href="/pt-BR/docs/Learn_web_development/Howto/Solve_JavaScript_problems">Solve common problems in your JavaScript code</a></li><li><a href="/en-US/docs/Learn_web_development/Howto/Web_mechanics" class="only-in-en-us">Web mechanics</a></li><li><a href="/en-US/docs/Learn_web_development/Howto/Tools_and_setup" class="only-in-en-us">Tools and setup</a></li><li><a href="/en-US/docs/Learn_web_development/Howto/Design_and_accessibility" class="only-in-en-us">Design and accessibility</a></li></ol></details></li><li><a href="/en-US/docs/Learn_web_development/About" class="only-in-en-us">About</a></li><li><a href="/en-US/docs/Learn_web_development/Educators" class="only-in-en-us">Resources for educators</a></li><li><a href="/en-US/docs/Learn_web_development/Changelog" class="only-in-en-us">Changelog</a></li></ol></div></div><section class="place side"></section></nav></aside><div class="toc-container"><aside class="toc"><nav><div class="document-toc-container"><section class="document-toc"><header><h2 class="document-toc-heading">Neste artigo</h2></header><ul class="document-toc-list"><li class="document-toc-item "><a class="document-toc-link" href="#ponto_de_partida">Ponto de partida</a></li><li class="document-toc-item "><a class="document-toc-link" href="#resumo_do_projeto">Resumo do projeto</a></li><li class="document-toc-item "><a class="document-toc-link" href="#passos_para_concluir">Passos para concluir</a></li><li class="document-toc-item "><a class="document-toc-link" href="#dicas_e_sugestões">Dicas e sugestões</a></li><li class="document-toc-item "><a class="document-toc-link" href="#avaliação">Avaliação</a></li></ul></section></div></nav></aside><section class="place side"></section></div></div><main id="content" class="main-content "><article class="main-page-content" lang="pt-BR"><header><h1>Galeria de Imagens</h1></header><div class="section-content"><ul class="prev-next"><li><a class="button secondary" href="/pt-BR/docs/Learn_web_development/Core/Scripting/Events"><span class="button-wrap"> Anterior </span></a></li><li><a class="button secondary" href="/pt-BR/docs/conflicting/Learn_web_development/Core/Scripting_fb235ec2f43049f379fbefbc9e0e7ee10637a460ab94430af2a806ab533a3580"><span class="button-wrap"> Menu: Elementos construtivos do Javascript</span></a></li></ul> <p>Agora que analisamos os blocos de construção fundamentais do JavaScript, testaremos seu conhecimento de loops, funções, condicionais e eventos, fazendo com que você crie um item bastante comum que você verá em muitos sites — uma galeria de imagens ativadas em JavaScript.</p> <figure class="table-container"><table class="learn-box standard-table"> <tbody> <tr> <th scope="row">Pré-requisitos:</th> <td> Antes de tentar esta avaliação, você já deve ter trabalhado em todos os artigos deste módulo. </td> </tr> <tr> <th scope="row">Objetivo:</th> <td> Para testar a compreensão de loops, funções, condicionais e eventos de JavaScript. </td> </tr> </tbody> </table></figure></div><section aria-labelledby="ponto_de_partida"><h2 id="ponto_de_partida"><a href="#ponto_de_partida">Ponto de partida</a></h2><div class="section-content"><p>Para começar esta avaliação, você deve <a href="https://github.com/mdn/learning-area/blob/master/javascript/building-blocks/gallery/gallery-start.zip?raw=true" class="external" target="_blank">pegar o arquivo ZIP</a> para o exemplo e descompactá-lo em algum lugar no seu computador.</p> <p>Como alternativa, você pode usar um site como o <a href="https://codepen.io/" class="external" target="_blank">CodePen</a>, <a href="https://jsfiddle.net/" class="external" target="_blank">JSFiddle</a> ou <a href="https://glitch.com/" class="external" target="_blank">Glitch</a> para fazer sua avaliação. Você pode colar o HTML, CSS e JavaScript em um desses editores on-line. Se o editor on-line que você está usando não tiver painéis JavaScript / CSS separados, sinta-se à vontade para colocar os elementos in-line <code><script></code> e <code><style></code> dentro da página HTML.</p></div></section><section aria-labelledby="resumo_do_projeto"><h2 id="resumo_do_projeto"><a href="#resumo_do_projeto">Resumo do projeto</a></h2><div class="section-content"><p>Você recebeu alguns recursos de HTML, CSS e imagem e algumas linhas de código JavaScript; você precisa escrever o JavaScript necessário para transformar isso em um programa de trabalho. O corpo do HTML se parece com isto:</p> <div class="code-example"><div class="example-header"><span class="language-name">html</span></div><pre class="brush: html notranslate"><code><h1>Image gallery example</h1> <div class="full-img"> <img class="displayed-img" src="images/pic1.jpg" /> <div class="overlay"></div> <button class="dark">Darken</button> </div> <div class="thumb-bar"></div> </code></pre></div> <p>O exemplo é assim:</p> <p><img src="/pt-BR/docs/Learn_web_development/Core/Scripting/Image_gallery/gallery.png" alt="" width="652" height="647" loading="lazy"></p> <p>As partes mais interessantes do arquivo CSS do exemplo:</p> <ul> <li>Absolutamente posicione os três elementos dentro do <code>full-img <div></code> — o <code><img></code> no qual a imagem em tamanho normal é exibida, um <code><div></code> vazio que é dimensionado para ser do mesmo tamanho que o <code><img></code> e colocado sobre a parte superior (isso é usado para aplicar um efeito de escurecimento à imagem através de uma cor de fundo semitransparente) e um <code><button></code> que é usado para controlar o efeito de escurecimento.</li> <li>Defina a largura de qualquer imagem dentro da thumb-bar <code>thumb-bar <div></code> (as chamadas imagens "thumbnail") para 20%, e flutue-as para a esquerda para que elas fiquem lado a lado em uma linha.</li> </ul> <p>Seu JavaScript precisa:</p> <ul> <li>Faça um loop em todas as imagens e, para cada uma, insira um elemento <code><img></code> dentro do <code>thumb-bar <div></code> que incorporará a imagem na página.</li> <li>Anexe um manipulador <code>onclick</code> para cada <code><img></code> dentro do <code>thumb-bar <div></code> para que, quando clicados, a imagem correspondente seja exibida no elemento <code>displayed-img <img></code>.</li> <li>Anexe um manipulador <code>onclick</code> ao <code><button></code> para que, ao ser clicado, um efeito de escurecimento seja aplicado à imagem em tamanho normal. Quando é clicado novamente, o efeito de escurecimento é removido novamente.</li> </ul> <p>Para lhe dar mais uma ideia, dê uma olhada no <a href="https://mdn.github.io/learning-area/javascript/building-blocks/gallery/" class="external" target="_blank">exemplo finalizado</a> (não espreite o código-fonte!)</p></div></section><section aria-labelledby="passos_para_concluir"><h2 id="passos_para_concluir"><a href="#passos_para_concluir">Passos para concluir</a></h2><div class="section-content"><p>As seções a seguir descrevem o que você precisa fazer.</p></div></section><section aria-labelledby="looping_através_das_imagens"><h3 id="looping_através_das_imagens"><a href="#looping_através_das_imagens">Looping através das imagens</a></h3><div class="section-content"><p>Já fornecemos a você linhas que armazenam uma referência à <code>thumb-bar <div></code> dentro de uma variável chamada <code>thumbBar</code>, cria um novo elemento <code><img></code> define seu atributo <code>src</code> como um valor de espaço reservado <code>xxx</code>, e acrescenta essa nova <code><img></code> elemento dentro do <code>thumbBar</code>.</p> <p>Você precisa:</p> <ol> <li>Coloque a seção de código abaixo do comentário "Looping through images" dentro de um loop que percorre todas as 5 imagens — você só precisa percorrer cinco números, um representando cada imagem.</li> <li>Em cada iteração de loop, substitua o valor de espaço reservado <code>xxx</code> por uma string que seja igual ao caminho para a imagem em cada caso. Estamos definindo o valor do atributo <code>src</code> para esse valor em cada caso. Tenha em mente que, em cada caso, a imagem está dentro do diretório de imagens e seu nome é <code>pic1.jpg</code>, <code>pic2.jpg</code>, etc.</li> </ol></div></section><section aria-labelledby="adicionando_um_manipulador_onclick_a_cada_imagem_em_miniatura"><h3 id="adicionando_um_manipulador_onclick_a_cada_imagem_em_miniatura"><a href="#adicionando_um_manipulador_onclick_a_cada_imagem_em_miniatura">Adicionando um manipulador onclick a cada imagem em miniatura</a></h3><div class="section-content"><p>Em cada iteração de loop, você precisa adicionar um manipulador <code>onclick</code> ao atual <code>newImage</code> — isso deve:</p> <ol> <li>Encontre o valor do atributo <code>src</code> da imagem atual. Isto pode ser feito executando a função <a href="/pt-BR/docs/Web/API/Element/getAttribute"><code>getAttribute()</code></a> no <code><img></code> em cada caso e passando um parâmetro de <code>"src"</code> em cada caso. Mas como conseguir a imagem? O uso do <code>newImage.getAttribute()</code> não funcionará, pois o loop é concluído antes de os manipuladores de eventos serem aplicados; fazer desta forma resultaria no retorno do valor <code>src</code> do último <code><img></code> para todos os casos. Para resolver isso, tenha em mente que, no caso de cada manipulador de eventos, o <code><img></code> é o destino do manipulador. Que tal obter as informações do objeto de evento?</li> <li>Rode uma função, passando o valor <code>src</code> retornado como um parâmetro. Você pode chamar essa função como quiser.</li> <li>Esta função do manipulador de eventos deve definir o valor do atributo <code>src</code> do <code>displayed-img <img></code> para o valor <code>src</code> passado como um parâmetro. Já fornecemos uma linha que armazena uma referência ao <code><img></code> relevante em uma variável chamada <code>displayedImg</code>. Note que queremos uma função nomeada definida aqui.</li> </ol></div></section><section aria-labelledby="escrevendo_um_manipulador_que_executa_o_botão_escurecer_clarear"><h3 id="escrevendo_um_manipulador_que_executa_o_botão_escurecer_clarear"><a href="#escrevendo_um_manipulador_que_executa_o_botão_escurecer_clarear">Escrevendo um manipulador que executa o botão escurecer / clarear</a></h3><div class="section-content"><p>Isso só deixa o nosso escurecer / clarear <code><button></code> — nós já fornecemos uma linha que armazena uma referência ao <code><button></code> em uma variável chamada <code>btn</code>. Você precisa adicionar um manipulador <code>onclick</code> que:</p> <ol> <li>Verifica o nome da classe atual definido no <code><button></code> — você pode novamente fazer isso usando <code>getAttribute()</code>.</li> <li>Se o nome da classe for <code>"dark"</code>, altera a classe <code><button></code> para <code>"light"</code> (usando <a href="/pt-BR/docs/Web/API/Element/setAttribute"><code>setAttribute()</code></a>), seu conteúdo de texto para "Lighten", e o <a href="/pt-BR/docs/Web/CSS/background-color"><code>background-color</code></a> da sobreposição <code><div></code> para <code>"rgba(0,0,0,0.5)"</code>.</li> <li>Se o nome da classe não for <code>"dark"</code>, a classe <code><button></code> será alterada para <code>"dark"</code>, o conteúdo de texto de volta para "Darken", e o <a href="/pt-BR/docs/Web/CSS/background-color"><code>background-color</code></a> da sobreposição <code><div></code> para <code>"rgba(0,0,0,0)"</code>.</li> </ol> <p>As linhas seguintes fornecem uma base para alcançar as mudanças estipuladas nos pontos 2 e 3 acima.</p> <div class="code-example"><div class="example-header"><span class="language-name">js</span></div><pre class="brush: js notranslate"><code>btn.setAttribute("class", xxx); btn.textContent = xxx; overlay.style.backgroundColor = xxx; </code></pre></div></div></section><section aria-labelledby="dicas_e_sugestões"><h2 id="dicas_e_sugestões"><a href="#dicas_e_sugestões">Dicas e sugestões</a></h2><div class="section-content"><ul> <li>Você não precisa editar o HTML ou CSS de forma alguma.</li> </ul></div></section><section aria-labelledby="avaliação"><h2 id="avaliação"><a href="#avaliação">Avaliação</a></h2><div class="section-content"><p>Se você está seguindo esta avaliação como parte de um curso organizado, você deve poder dar seu trabalho ao seu professor / mentor para marcação. Se você é auto-didata, então pode obter o guia de marcação com bastante facilidade, perguntando no tópico de <a href="https://discourse.mozilla.org/t/image-gallery-assessment/24687" class="external" target="_blank">discussão sobre este exercício</a>, ou no canal <a href="irc://irc.mozilla.org/mdn">#mdn</a> IRC da <a href="https://wiki.mozilla.org/IRC" class="external" target="_blank">Mozilla IRC</a>. Tente o exercício primeiro — não há nada a ganhar com a trapaça!</p> <ul class="prev-next"><li><a class="button secondary" href="/pt-BR/docs/Learn_web_development/Core/Scripting/Events"><span class="button-wrap"> Anterior </span></a></li><li><a class="button secondary" href="/pt-BR/docs/conflicting/Learn_web_development/Core/Scripting_fb235ec2f43049f379fbefbc9e0e7ee10637a460ab94430af2a806ab533a3580"><span class="button-wrap"> Menu: Elementos construtivos do Javascript</span></a></li></ul></div></section></article><aside class="article-footer"><div class="article-footer-inner"><div class="svg-container"><svg xmlns="http://www.w3.org/2000/svg" width="162" height="162" viewBox="0 0 162 162" fill="none" role="none"><mask id="b" fill="#fff"><path d="M97.203 47.04c8.113-7.886 18.004-13.871 28.906-17.492a78 78 0 0 1 33.969-3.39c11.443 1.39 22.401 5.295 32.024 11.411s17.656 14.28 23.476 23.86c5.819 9.579 9.269 20.318 10.083 31.385a69.85 69.85 0 0 1-5.387 32.44c-4.358 10.272-11.115 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class="footer-moz-link" target="_blank" rel="noopener noreferrer">Cookies</a></li><li class="footer-moz-item"><a href="https://www.mozilla.org/about/legal/terms/mozilla" class="footer-moz-link" target="_blank" rel="noopener noreferrer">Legal</a></li><li class="footer-moz-item"><a href="https://www.mozilla.org/about/governance/policies/participation/" class="footer-moz-link" target="_blank" rel="noopener noreferrer">Community Participation Guidelines</a></li></ul></div><div class="page-footer-legal"><p id="license" class="page-footer-legal-text">Visit <a href="https://www.mozilla.org" target="_blank" rel="noopener noreferrer">Mozilla Corporation’s</a> not-for-profit parent, the <a target="_blank" rel="noopener noreferrer" href="https://foundation.mozilla.org/">Mozilla Foundation</a>.<br/>Portions of this content are ©1998–2025 by individual mozilla.org contributors. Content available under <a href="/pt-BR/docs/MDN/Writing_guidelines/Attrib_copyright_license">a Creative Commons license</a>.</p></div></div></footer></div><script type="application/json" id="hydration">{"url":"/pt-BR/docs/Learn_web_development/Core/Scripting/Image_gallery","doc":{"body":[{"type":"prose","value":{"id":null,"title":null,"isH3":false,"content":"<ul class=\"prev-next\"><li><a class=\"button secondary\" href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Events\"><span class=\"button-wrap\"> Anterior </span></a></li><li><a class=\"button secondary\" href=\"/pt-BR/docs/conflicting/Learn_web_development/Core/Scripting_fb235ec2f43049f379fbefbc9e0e7ee10637a460ab94430af2a806ab533a3580\"><span class=\"button-wrap\"> Menu: Elementos construtivos do Javascript</span></a></li></ul>\n<p>Agora que analisamos os blocos de construção fundamentais do JavaScript, testaremos seu conhecimento de loops, funções, condicionais e eventos, fazendo com que você crie um item bastante comum que você verá em muitos sites — uma galeria de imagens ativadas em JavaScript.</p>\n<figure class=\"table-container\"><table class=\"learn-box standard-table\">\n <tbody>\n <tr>\n <th scope=\"row\">Pré-requisitos:</th>\n <td>\n Antes de tentar esta avaliação, você já deve ter trabalhado em todos os\n artigos deste módulo.\n </td>\n </tr>\n <tr>\n <th scope=\"row\">Objetivo:</th>\n <td>\n Para testar a compreensão de loops, funções, condicionais e eventos de\n JavaScript.\n </td>\n </tr>\n </tbody>\n</table></figure>"}},{"type":"prose","value":{"id":"ponto_de_partida","title":"Ponto de partida","isH3":false,"content":"<p>Para começar esta avaliação, você deve <a href=\"https://github.com/mdn/learning-area/blob/master/javascript/building-blocks/gallery/gallery-start.zip?raw=true\" class=\"external\" target=\"_blank\">pegar o arquivo ZIP</a> para o exemplo e descompactá-lo em algum lugar no seu computador.</p>\n<p>Como alternativa, você pode usar um site como o <a href=\"https://codepen.io/\" class=\"external\" target=\"_blank\">CodePen</a>, <a href=\"https://jsfiddle.net/\" class=\"external\" target=\"_blank\">JSFiddle</a> ou <a href=\"https://glitch.com/\" class=\"external\" target=\"_blank\">Glitch</a> para fazer sua avaliação. Você pode colar o HTML, CSS e JavaScript em um desses editores on-line. Se o editor on-line que você está usando não tiver painéis JavaScript / CSS separados, sinta-se à vontade para colocar os elementos in-line <code><script></code> e <code><style></code> dentro da página HTML.</p>"}},{"type":"prose","value":{"id":"resumo_do_projeto","title":"Resumo do projeto","isH3":false,"content":"<p>Você recebeu alguns recursos de HTML, CSS e imagem e algumas linhas de código JavaScript; você precisa escrever o JavaScript necessário para transformar isso em um programa de trabalho. O corpo do HTML se parece com isto:</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">html</span></div><pre class=\"brush: html notranslate\"><code><h1>Image gallery example</h1>\n\n<div class=\"full-img\">\n <img class=\"displayed-img\" src=\"images/pic1.jpg\" />\n <div class=\"overlay\"></div>\n <button class=\"dark\">Darken</button>\n</div>\n\n<div class=\"thumb-bar\"></div>\n</code></pre></div>\n<p>O exemplo é assim:</p>\n<p><img src=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Image_gallery/gallery.png\" alt=\"\" width=\"652\" height=\"647\" loading=\"lazy\"></p>\n<p>As partes mais interessantes do arquivo CSS do exemplo:</p>\n<ul>\n<li>Absolutamente posicione os três elementos dentro do <code>full-img <div></code> — o <code><img></code> no qual a imagem em tamanho normal é exibida, um <code><div></code> vazio que é dimensionado para ser do mesmo tamanho que o <code><img></code> e colocado sobre a parte superior (isso é usado para aplicar um efeito de escurecimento à imagem através de uma cor de fundo semitransparente) e um <code><button></code> que é usado para controlar o efeito de escurecimento.</li>\n<li>Defina a largura de qualquer imagem dentro da thumb-bar <code>thumb-bar <div></code> (as chamadas imagens \"thumbnail\") para 20%, e flutue-as para a esquerda para que elas fiquem lado a lado em uma linha.</li>\n</ul>\n<p>Seu JavaScript precisa:</p>\n<ul>\n<li>Faça um loop em todas as imagens e, para cada uma, insira um elemento <code><img></code> dentro do <code>thumb-bar <div></code> que incorporará a imagem na página.</li>\n<li>Anexe um manipulador <code>onclick</code> para cada <code><img></code> dentro do <code>thumb-bar <div></code> para que, quando clicados, a imagem correspondente seja exibida no elemento <code>displayed-img <img></code>.</li>\n<li>Anexe um manipulador <code>onclick</code> ao <code><button></code> para que, ao ser clicado, um efeito de escurecimento seja aplicado à imagem em tamanho normal. Quando é clicado novamente, o efeito de escurecimento é removido novamente.</li>\n</ul>\n<p>Para lhe dar mais uma ideia, dê uma olhada no <a href=\"https://mdn.github.io/learning-area/javascript/building-blocks/gallery/\" class=\"external\" target=\"_blank\">exemplo finalizado</a> (não espreite o código-fonte!)</p>"}},{"type":"prose","value":{"id":"passos_para_concluir","title":"Passos para concluir","isH3":false,"content":"<p>As seções a seguir descrevem o que você precisa fazer.</p>"}},{"type":"prose","value":{"id":"looping_através_das_imagens","title":"Looping através das imagens","isH3":true,"content":"<p>Já fornecemos a você linhas que armazenam uma referência à <code>thumb-bar <div></code> dentro de uma variável chamada <code>thumbBar</code>, cria um novo elemento <code><img></code> define seu atributo <code>src</code> como um valor de espaço reservado <code>xxx</code>, e acrescenta essa nova <code><img></code> elemento dentro do <code>thumbBar</code>.</p>\n<p>Você precisa:</p>\n<ol>\n<li>Coloque a seção de código abaixo do comentário \"Looping through images\" dentro de um loop que percorre todas as 5 imagens — você só precisa percorrer cinco números, um representando cada imagem.</li>\n<li>Em cada iteração de loop, substitua o valor de espaço reservado <code>xxx</code> por uma string que seja igual ao caminho para a imagem em cada caso. Estamos definindo o valor do atributo <code>src</code> para esse valor em cada caso. Tenha em mente que, em cada caso, a imagem está dentro do diretório de imagens e seu nome é <code>pic1.jpg</code>, <code>pic2.jpg</code>, etc.</li>\n</ol>"}},{"type":"prose","value":{"id":"adicionando_um_manipulador_onclick_a_cada_imagem_em_miniatura","title":"Adicionando um manipulador onclick a cada imagem em miniatura","isH3":true,"content":"<p>Em cada iteração de loop, você precisa adicionar um manipulador <code>onclick</code> ao atual <code>newImage</code> — isso deve:</p>\n<ol>\n<li>Encontre o valor do atributo <code>src</code> da imagem atual. Isto pode ser feito executando a função <a href=\"/pt-BR/docs/Web/API/Element/getAttribute\"><code>getAttribute()</code></a> no <code><img></code> em cada caso e passando um parâmetro de <code>\"src\"</code> em cada caso. Mas como conseguir a imagem? O uso do <code>newImage.getAttribute()</code> não funcionará, pois o loop é concluído antes de os manipuladores de eventos serem aplicados; fazer desta forma resultaria no retorno do valor <code>src</code> do último <code><img></code> para todos os casos. Para resolver isso, tenha em mente que, no caso de cada manipulador de eventos, o <code><img></code> é o destino do manipulador. Que tal obter as informações do objeto de evento?</li>\n<li>Rode uma função, passando o valor <code>src</code> retornado como um parâmetro. Você pode chamar essa função como quiser.</li>\n<li>Esta função do manipulador de eventos deve definir o valor do atributo <code>src</code> do <code>displayed-img <img></code> para o valor <code>src</code> passado como um parâmetro. Já fornecemos uma linha que armazena uma referência ao <code><img></code> relevante em uma variável chamada <code>displayedImg</code>. Note que queremos uma função nomeada definida aqui.</li>\n</ol>"}},{"type":"prose","value":{"id":"escrevendo_um_manipulador_que_executa_o_botão_escurecer_clarear","title":"Escrevendo um manipulador que executa o botão escurecer / clarear","isH3":true,"content":"<p>Isso só deixa o nosso escurecer / clarear <code><button></code> — nós já fornecemos uma linha que armazena uma referência ao <code><button></code> em uma variável chamada <code>btn</code>. Você precisa adicionar um manipulador <code>onclick</code> que:</p>\n<ol>\n<li>Verifica o nome da classe atual definido no <code><button></code> — você pode novamente fazer isso usando <code>getAttribute()</code>.</li>\n<li>Se o nome da classe for <code>\"dark\"</code>, altera a classe <code><button></code> para <code>\"light\"</code> (usando <a href=\"/pt-BR/docs/Web/API/Element/setAttribute\"><code>setAttribute()</code></a>), seu conteúdo de texto para \"Lighten\", e o <a href=\"/pt-BR/docs/Web/CSS/background-color\"><code>background-color</code></a> da sobreposição <code><div></code> para <code>\"rgba(0,0,0,0.5)\"</code>.</li>\n<li>Se o nome da classe não for <code>\"dark\"</code>, a classe <code><button></code> será alterada para <code>\"dark\"</code>, o conteúdo de texto de volta para \"Darken\", e o <a href=\"/pt-BR/docs/Web/CSS/background-color\"><code>background-color</code></a> da sobreposição <code><div></code> para <code>\"rgba(0,0,0,0)\"</code>.</li>\n</ol>\n<p>As linhas seguintes fornecem uma base para alcançar as mudanças estipuladas nos pontos 2 e 3 acima.</p>\n<div class=\"code-example\"><div class=\"example-header\"><span class=\"language-name\">js</span></div><pre class=\"brush: js notranslate\"><code>btn.setAttribute(\"class\", xxx);\nbtn.textContent = xxx;\noverlay.style.backgroundColor = xxx;\n</code></pre></div>"}},{"type":"prose","value":{"id":"dicas_e_sugestões","title":"Dicas e sugestões","isH3":false,"content":"<ul>\n<li>Você não precisa editar o HTML ou CSS de forma alguma.</li>\n</ul>"}},{"type":"prose","value":{"id":"avaliação","title":"Avaliação","isH3":false,"content":"<p>Se você está seguindo esta avaliação como parte de um curso organizado, você deve poder dar seu trabalho ao seu professor / mentor para marcação. Se você é auto-didata, então pode obter o guia de marcação com bastante facilidade, perguntando no tópico de <a href=\"https://discourse.mozilla.org/t/image-gallery-assessment/24687\" class=\"external\" target=\"_blank\">discussão sobre este exercício</a>, ou no canal <a href=\"irc://irc.mozilla.org/mdn\">#mdn</a> IRC da <a href=\"https://wiki.mozilla.org/IRC\" class=\"external\" target=\"_blank\">Mozilla IRC</a>. Tente o exercício primeiro — não há nada a ganhar com a trapaça!</p>\n<ul class=\"prev-next\"><li><a class=\"button secondary\" href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Events\"><span class=\"button-wrap\"> Anterior </span></a></li><li><a class=\"button secondary\" href=\"/pt-BR/docs/conflicting/Learn_web_development/Core/Scripting_fb235ec2f43049f379fbefbc9e0e7ee10637a460ab94430af2a806ab533a3580\"><span class=\"button-wrap\"> Menu: Elementos construtivos do Javascript</span></a></li></ul>"}}],"isActive":true,"isMarkdown":true,"isTranslated":true,"locale":"pt-BR","mdn_url":"/pt-BR/docs/Learn_web_development/Core/Scripting/Image_gallery","modified":"1970-01-01T00:00:00.000Z","native":"Português (do Brasil)","noIndexing":false,"other_translations":[{"locale":"en-US","title":"Challenge: Image gallery","native":"English (US)"},{"locale":"de","title":"Herausforderung: Bildergalerie","native":"Deutsch"},{"locale":"fr","title":"Galerie d'images","native":"Français"},{"locale":"ja","title":"課題: イメージギャラリー","native":"日本語"},{"locale":"ko","title":"이미지 갤러리","native":"한국어"},{"locale":"ru","title":"Галерея изображений","native":"Русский"},{"locale":"zh-CN","title":"图片库","native":"中文 (简体)"},{"locale":"zh-TW","title":"影像圖庫","native":"正體中文 (繁體)"}],"pageTitle":"Galeria de Imagens - Aprendendo desenvolvimento web | MDN","parents":[{"uri":"/pt-BR/docs/Learn_web_development","title":"Aprendendo desenvolvimento web"},{"uri":"/en-US/docs/Learn_web_development/Core","title":"Core learning modules"},{"uri":"/pt-BR/docs/Learn_web_development/Core/Scripting","title":"Primeiros passos com JavaScript"},{"uri":"/pt-BR/docs/Learn_web_development/Core/Scripting/Image_gallery","title":"Galeria de Imagens"}],"popularity":null,"short_title":"Galeria de Imagens","sidebarHTML":"<ol><li class=\"section\"><a href=\"/en-US/docs/Learn_web_development/Getting_started\" class=\"only-in-en-us\">Getting started modules</a></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Getting_started/Environment_setup\" class=\"only-in-en-us\">Environment setup</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Getting_started/Environment_setup/Installing_software\">Instalando os programas básicos</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Getting_started/Environment_setup/Browsing_the_web\">Qual a diferença entre página web, site, servidor web e mecanismo de busca?</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Environment_setup/Code_editors\" class=\"only-in-en-us\">Code editors</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Getting_started/Environment_setup/Dealing_with_files\">Lidando com arquivos</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Environment_setup/Command_line\" class=\"only-in-en-us\">Command line crash course</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Getting_started/Your_first_website\">Your first website</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Getting_started/Your_first_website/What_will_your_website_look_like\">Como será o seu site?</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Getting_started/Your_first_website/Creating_the_content\">HTML básico</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Getting_started/Your_first_website/Styling_the_content\">CSS básico</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Getting_started/Your_first_website/Adding_interactivity\">Noções básicas de JavaScript</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Getting_started/Your_first_website/Publishing_your_website\">Publicando seu site</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Getting_started/Web_standards\" class=\"only-in-en-us\">Web standards</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Getting_started/Web_standards/How_the_web_works\">Como a Web funciona</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Getting_started/Web_standards/The_web_standards_model\">A web e seus padrões</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Web_standards/How_browsers_load_websites\" class=\"only-in-en-us\">How browsers load websites</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Getting_started/Soft_skills\" class=\"only-in-en-us\">Soft skills</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Research_and_learning\" class=\"only-in-en-us\">Research and learning</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Collaboration_and_teamwork\" class=\"only-in-en-us\">Collaboration and teamwork</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Workflows_and_processes\" class=\"only-in-en-us\">Workflows and processes</a></li><li><a href=\"/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Job_interviews\" class=\"only-in-en-us\">Succeeding in job interviews</a></li></ol></details></li><li class=\"section\"><a href=\"/en-US/docs/Learn_web_development/Core\" class=\"only-in-en-us\">Core modules</a></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Core/Structuring_content\">Structuring content with HTML</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Structuring_content/Basic_HTML_syntax\">Iniciando com HTML</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Structuring_content/Webpage_metadata\">O que está no cabeçalho? Metadados em HTML</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Structuring_content/Headings_and_paragraphs\">Fundamentos do texto em HTML</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Emphasis_and_importance\" class=\"only-in-en-us\">Emphasis and importance</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Lists\" class=\"only-in-en-us\">Lists</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Structuring_content/Structuring_documents\">Estrutura de documento e sites</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Structuring_content/Advanced_text_features\">Formatação avançada de texto</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Structuring_content/Creating_links\">Criando hyperlinks</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Marking_up_a_letter\" class=\"only-in-en-us\">Challenge: Marking up a letter</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Structuring_a_page_of_content\" class=\"only-in-en-us\">Challenge: Structuring a page of content</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Structuring_content/HTML_images\">Imagens no HTML</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Structuring_content/HTML_video_and_audio\">Conteúdo de vídeo e áudio</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Mozilla_splash_page\" class=\"only-in-en-us\">Challenge: Mozilla splash page</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Structuring_content/HTML_table_basics\">HTML table basics</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Table_accessibility\" class=\"only-in-en-us\">HTML table accessibility</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/Planet_data_table\" class=\"only-in-en-us\">Challenge: Structuring a planet data table</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_forms\" class=\"only-in-en-us\">Forms and buttons in HTML</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Structuring_content/Debugging_HTML\">Debugging HTML</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Core/Styling_basics\">CSS styling basics</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Styling_basics/What_is_CSS\">O que é CSS?</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Styling_basics/Getting_started\">Como CSS é estruturado</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Styling_basics/Styling_a_bio_page\">Usando seu novo conhecimento</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Styling_basics/Basic_selectors\">CSS selectors</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Styling_basics/Attribute_selectors\">Seletores de atributo</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Pseudo_classes_and_elements\" class=\"only-in-en-us\">Pseudo-classes and pseudo-elements</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Combinators\" class=\"only-in-en-us\">Combinators</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Styling_basics/Box_model\">The box model</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Styling_basics/Handling_conflicts\">Cascata, especificidade e herança</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Values_and_units\" class=\"only-in-en-us\">CSS values and units</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Sizing\" class=\"only-in-en-us\">Sizing items in CSS</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Backgrounds_and_borders\" class=\"only-in-en-us\">Backgrounds and borders</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Overflow\" class=\"only-in-en-us\">Overflowing content</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Images_media_forms\" class=\"only-in-en-us\">Images, media, and form elements</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Tables\" class=\"only-in-en-us\">Styling tables</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Debugging_CSS\" class=\"only-in-en-us\">Debugging CSS</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Fundamental_CSS_comprehension\" class=\"only-in-en-us\">Challenge: Fundamental CSS comprehension</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Fancy_letterheaded_paper\" class=\"only-in-en-us\">Challenge: Creating fancy letterheaded paper</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Styling_basics/Cool-looking_box\" class=\"only-in-en-us\">Challenge: A cool-looking box</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Core/Text_styling\">CSS text styling</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Core/Text_styling/Fundamentals\" class=\"only-in-en-us\">Fundamental text and font styling</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Text_styling/Styling_lists\">Manipulando Listas</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Text_styling/Styling_links\" class=\"only-in-en-us\">Styling links</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Text_styling/Web_fonts\" class=\"only-in-en-us\">Web fonts</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Text_styling/Typesetting_a_homepage\" class=\"only-in-en-us\">Challenge: Typesetting a community school homepage</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Core/CSS_layout\">Esquemas CSS</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Core/CSS_layout/Introduction\">Fluxo Normal</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Floats\" class=\"only-in-en-us\">Floats</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Positioning\" class=\"only-in-en-us\">Positioning</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/CSS_layout/Flexbox\">Flexbox</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Grids\" class=\"only-in-en-us\">CSS grid layout</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/CSS_layout/Responsive_Design\">Design Responsivo</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Media_queries\" class=\"only-in-en-us\">Media query fundamentals</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/CSS_layout/Fundamental_Layout_Comprehension\" class=\"only-in-en-us\">Challenge: Fundamental layout comprehension</a></li></ol></details></li><li class=\"toggle\"><details open=\"\"><summary><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting\">Dynamic scripting with JavaScript</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/What_is_JavaScript\">O que é JavaScript?</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/A_first_splash\">Um primeiro mergulho no JavaScript</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/What_went_wrong\">O que deu errado? Resolvendo problemas no JavaScript</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Variables\">Armazenando as informações que você precisa — Variáveis</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Math\">Matemática básica no JavaScript — números e operadores</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Strings\">Trabalhando com texto — strings em JavaScript</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Useful_string_methods\">Métodos úteis de string</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Arrays\">Arrays</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Silly_story_generator\">Gerador de histórias bobas</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Conditionals\">Tomando decisões no seu código — condicionais</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Loops\">Código em loop</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Functions\">Funções — blocos reutilizáveis de código</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Build_your_own_function\">Construa sua própria função</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Return_values\">Valores de retorno de função</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Events\">Introdução a eventos</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Event_bubbling\">Comparativo entre Event Targets</a></li><li><em><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Image_gallery\" aria-current=\"page\">Galeria de Imagens</a></em></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Object_basics\">O básico sobre objetos JavaScript</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/DOM_scripting\">JavaScript e CSS</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/Network_requests\">AJAX</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Scripting/JSON\">Trabalhando com JSON</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript\" class=\"only-in-en-us\">Debugging JavaScript and handling errors</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Core/Frameworks_libraries\">JavaScript frameworks and libraries</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/Introduction\" class=\"only-in-en-us\">Introduction to client-side frameworks</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/Main_features\" class=\"only-in-en-us\">Framework main features</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Frameworks_libraries/React_getting_started\">Começando com React</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_todo_list_beginning\" class=\"only-in-en-us\">Beginning our React todo list</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_components\" class=\"only-in-en-us\">Componentizing our React app</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_interactivity_events_state\" class=\"only-in-en-us\">React interactivity: Events and state</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_interactivity_filtering_conditional_rendering\" class=\"only-in-en-us\">React interactivity: Editing, filtering, conditional rendering</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_accessibility\" class=\"only-in-en-us\">Accessibility in React</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_resources\" class=\"only-in-en-us\">React resources</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Core/Accessibility\">Accessibility</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/What_is_accessibility\" class=\"only-in-en-us\">What is accessibility?</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/Tooling\" class=\"only-in-en-us\">Accessibility tooling and assistive technology</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Accessibility/HTML\">HTML: Boas práticas em acessibilidade</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/CSS_and_JavaScript\" class=\"only-in-en-us\">CSS and JavaScript accessibility best practices</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/WAI-ARIA_basics\" class=\"only-in-en-us\">WAI-ARIA basics</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/Multimedia\" class=\"only-in-en-us\">Accessible multimedia</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Accessibility/Mobile\" class=\"only-in-en-us\">Mobile accessibility</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Core/Accessibility/Accessibility_troubleshooting\">Avaliação: solucionando problemas de acessibilidade</a></li></ol></details></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Design_for_developers\" class=\"only-in-en-us\">Design for developers</a></li><li><a href=\"/en-US/docs/Learn_web_development/Core/Version_control\" class=\"only-in-en-us\">Version control</a></li><li class=\"section\"><a href=\"/en-US/docs/Learn_web_development/Extensions\" class=\"only-in-en-us\">Extension modules</a></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects\">Advanced JavaScript objects</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes\">Protótipos de objetos</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object-oriented_programming\" class=\"only-in-en-us\">Object-oriented programming</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript\">Herança em JavaScript</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_building_practice\">Prática de construção de objetos</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Adding_bouncing_balls_features\">Adicionando recursos à nossa demonstração de bolas pulantes</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Client-side_APIs\">APIs Web na aplicação Cliente</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Client-side_APIs/Introduction\">Introdução às Web APIs</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Video_and_audio_APIs\" class=\"only-in-en-us\">Video and Audio APIs</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Drawing_graphics\" class=\"only-in-en-us\">Drawing graphics</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Client-side_APIs/Client-side_storage\">Client-side storage</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Third_party_APIs\" class=\"only-in-en-us\">Third-party APIs</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Async_JS\">Asynchronous JavaScript</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Async_JS/Introducing\">Introdução ao JavaScript Async</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Async_JS/Promises\">Como usar Promises</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Async_JS/Implementing_a_promise-based_API\" class=\"only-in-en-us\">How to implement a promise-based API</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Async_JS/Introducing_workers\" class=\"only-in-en-us\">Introducing workers</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Async_JS/Sequencing_animations\" class=\"only-in-en-us\">Challenge: Sequencing animations</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Forms\">Web forms — Working with user data</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Forms/Your_first_form\">Meu primeiro formulário HTML</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Forms/How_to_structure_a_web_form\">Como estruturar um formulário HTML</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/Basic_native_form_controls\" class=\"only-in-en-us\">Basic native form controls</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/HTML5_input_types\" class=\"only-in-en-us\">The HTML5 input types</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/Other_form_controls\" class=\"only-in-en-us\">Other form controls</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/Styling_web_forms\" class=\"only-in-en-us\">Styling web forms</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/Advanced_form_styling\" class=\"only-in-en-us\">Advanced form styling</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Forms/UI_pseudo-classes\" class=\"only-in-en-us\">UI pseudo-classes</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Forms/Form_validation\">Form data validation</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Forms/Sending_and_retrieving_form_data\">Sending form data</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_tools\" class=\"only-in-en-us\">Understanding client-side tools</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Overview\" class=\"only-in-en-us\">Client-side tooling overview</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Package_management\" class=\"only-in-en-us\">Package management basics</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Introducing_complete_toolchain\" class=\"only-in-en-us\">Introducing a complete toolchain</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Deployment\" class=\"only-in-en-us\">Deploying our app</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side\">Server-side websites</a></summary><ol><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/First_steps\">Server-side first steps</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/First_steps/Introduction\">Introdução ao lado servidor</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/First_steps/Client-Server_overview\">Visão geral do cliente-servidor</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Web_frameworks\" class=\"only-in-en-us\">Server-side web frameworks</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/First_steps/Website_security\">Segurança em aplicação web</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django\">Framework Web Django (Python)</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Introduction\">Introdução ao Django</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/development_environment\">Configurando um ambiente de desenvolvimento Django</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Tutorial_local_library_website\">Tutorial Django: Website da Biblioteca Local</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/skeleton_website\">Django Tutorial Parte 2: Criando o \"esqueleto\" de um site</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Models\">Tutorial Django Parte 3: Usando models</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Admin_site\">Tutorial Django Parte 4: Django admin site</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Home_page\">Django Tutorial Parte 5: Criando nossa home page</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Generic_views\">Tutorial Django Parte 6: Lista genérica e detail views</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Sessions\">Tutorial Django Parte 7: Sessões</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Authentication\">Tutorial Django Parte 8: Autenticação de usuário e permissões</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Forms\">Tutorial Django Parte 9: Trabalhando com formulários</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Testing\">Tutorial Django Parte 10: Testando uma aplicação web Django</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/Deployment\">Tutorial Django Parte 11: Hospedando Django para produção</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Django/web_application_security\">Segurança de aplicações web Django</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Django/django_assessment_blog\" class=\"only-in-en-us\">Assessment: DIY Django mini blog</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs\">Express web framework (Node.js)</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Introduction\">Introdução Express/Node</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/development_environment\">Configurando o Node como ambiente de desenvolvimento</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Tutorial_local_library_website\">Express: Tutorial para criar o site de uma Biblioteca Local</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/skeleton_website\">Express Tutorial Parte 2: Criando a estrutura do website</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/mongoose\">Tutorial Express Parte 3: Usando um banco de dados (com Mongoose)</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/routes\" class=\"only-in-en-us\">Express Tutorial Part 4: Routes and controllers</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Displaying_data\" class=\"only-in-en-us\">Express Tutorial Part 5: Displaying library data</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/forms\" class=\"only-in-en-us\">Express Tutorial Part 6: Working with forms</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/deployment\" class=\"only-in-en-us\">Express Tutorial Part 7: Deploying to production</a></li></ol></details></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance\" class=\"only-in-en-us\">Web performance</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/why_web_performance\" class=\"only-in-en-us\">The \"why\" of web performance</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/What_is_web_performance\" class=\"only-in-en-us\">What is web performance?</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/Perceived_performance\" class=\"only-in-en-us\">Perceived performance</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/Measuring_performance\" class=\"only-in-en-us\">Measuring performance</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/Multimedia\" class=\"only-in-en-us\">Multimedia: Images</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/video\" class=\"only-in-en-us\">Multimedia: video</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/JavaScript\" class=\"only-in-en-us\">JavaScript performance optimization</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/HTML\" class=\"only-in-en-us\">HTML performance optimization</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/CSS\" class=\"only-in-en-us\">CSS performance optimization</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Performance/business_case_for_performance\" class=\"only-in-en-us\">The business case for web performance</a></li></ol></details></li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Extensions/Testing\">Testing</a></summary><ol><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing/Introduction\" class=\"only-in-en-us\">Introduction to cross-browser testing</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing/Testing_strategies\" class=\"only-in-en-us\">Strategies for carrying out testing</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing/HTML_and_CSS\" class=\"only-in-en-us\">Handling common HTML and CSS problems</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing/Feature_detection\" class=\"only-in-en-us\">Implementing feature detection</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing/Automated_testing\" class=\"only-in-en-us\">Introduction to automated testing</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Testing/Your_own_automation_environment\" class=\"only-in-en-us\">Setting up your own test automation environment</a></li></ol></details></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Transform_animate\" class=\"only-in-en-us\">Transform and animate CSS</a></li><li><a href=\"/en-US/docs/Learn_web_development/Extensions/Security_privacy\" class=\"only-in-en-us\">Security and privacy</a></li><li class=\"section\">Mais recursos</li><li class=\"toggle\"><details><summary><a href=\"/pt-BR/docs/Learn_web_development/Howto\">How to solve common problems</a></summary><ol><li><a href=\"/pt-BR/docs/Learn_web_development/Howto/Solve_HTML_problems\">Use HTML para resolver problemas comuns</a></li><li><a href=\"/en-US/docs/Learn_web_development/Howto/Solve_CSS_problems\" class=\"only-in-en-us\">Solve common CSS problems</a></li><li><a href=\"/pt-BR/docs/Learn_web_development/Howto/Solve_JavaScript_problems\">Solve common problems in your JavaScript code</a></li><li><a href=\"/en-US/docs/Learn_web_development/Howto/Web_mechanics\" class=\"only-in-en-us\">Web mechanics</a></li><li><a href=\"/en-US/docs/Learn_web_development/Howto/Tools_and_setup\" class=\"only-in-en-us\">Tools and setup</a></li><li><a href=\"/en-US/docs/Learn_web_development/Howto/Design_and_accessibility\" class=\"only-in-en-us\">Design and accessibility</a></li></ol></details></li><li><a href=\"/en-US/docs/Learn_web_development/About\" class=\"only-in-en-us\">About</a></li><li><a href=\"/en-US/docs/Learn_web_development/Educators\" class=\"only-in-en-us\">Resources for educators</a></li><li><a href=\"/en-US/docs/Learn_web_development/Changelog\" class=\"only-in-en-us\">Changelog</a></li></ol>","source":{"folder":"pt-br/learn_web_development/core/scripting/image_gallery","github_url":"https://github.com/mdn/translated-content/blob/main/files/pt-br/learn_web_development/core/scripting/image_gallery/index.md","last_commit_url":"https://github.com/mdn/translated-content/commit/","filename":"index.md"},"summary":"Agora que analisamos os blocos de construção fundamentais do JavaScript, testaremos seu conhecimento de loops, funções, condicionais e eventos, fazendo com que você crie um item bastante comum que você verá em muitos sites — uma galeria de imagens ativadas em JavaScript.","title":"Galeria de Imagens","toc":[{"text":"Ponto de partida","id":"ponto_de_partida"},{"text":"Resumo do projeto","id":"resumo_do_projeto"},{"text":"Passos para concluir","id":"passos_para_concluir"},{"text":"Dicas e sugestões","id":"dicas_e_sugestões"},{"text":"Avaliação","id":"avaliação"}],"pageType":"learn-module-assessment"}}</script></body></html>