Tutorials on Web Components

Before Shadow DOM, you needed a framework to encapsulate component templates or styling. Shadow DOM was a game-changer because it allows you to code UI components without their logic clashing with other components using just the web platform. Shadow DOM poses challenges when HTML elements encapsulated by Shadow DOM need to participate in a form. In this post, I'll provide an overview of form-associated custom elements. Form-associated custom elements is a web specification that allows engineers to code custom form controls that report value and validity to HTMLFormElement , while also promoting a fully accessible user experience. With the encapsulation provided by Shadow DOM, engineers can code UI components where the CSS styling doesn't collide with other components. Shadow DOM provides a DOM tree for an element separated from the rest of the Document Object Model (DOM). The separation of concerns promoted by Shadow DOM is a boon for coding reusable UI components.

In this capstone tutorial, we're going to actually use the micro-library in app code so you can see how the micro-library makes things easier for developers in real world development. In the previous steps of this 4-part tutorial, this is what we accomplished: In this final tutorial, we will now refactor an example component to use the @Component decorator and the attachShadow function from our micro-library.

Here is Part 3/4 of our tutorial series on building a JavaScript micro-library for creating your apps with Web Components. As I pointed out in previous lessons, the micro-library eases the path to development with Web Components, automating a lot of the work so developers can build their apps faster. Here's what we covered so far: Now in this tutorial, Part 3, we will automate another piece of functionality for classes that use our decorator. In this case, we'll automatically attach a Shadow DOM to those classes so that the user of the library does not have to manually create a Shadow DOM for their custom elements.

As we covered in the previous tutorial , a micro-library helps developers implement common features more quickly than using the web APIs directly. Now in this tutorial, we will code our class decorator that allows our classes to instantly gain new features without writing the code for them every time. The class decorator eliminates boilerplate and allows users of the micro-library to focus on higher-level concepts while delegating common class setups to the micro-library. Implementing a class decorator is going to significantly improve the developer experience, allowing developers to code Web Components faster. We'll enhance the class-based implementation which custom elements rely on by cleaning up each constructor .

If you've ever wondered how libraries like React , Preact , or Svelte work under the hood, this is a great exploration of what you need to know. Using Web Components means that your own micro-library, which we build in this series, will work easily with any JavaScript codebase. This achieves greater levels of code reuse. Let's dive in. When building with Web Components, you will rely heavily on the set of specifications that make up Web Components: The main benefits Web Components bring to the table: reuse, interoperable, accessible, having a long lifespan, are due to their reliance on browser specifications. Had we adopted a library or framework, we might have lost some or all of these characteristics in the user interfaces built with it. UI components coded with some libraries aren't interoperable with other JavaScript libraries or frameworks, which puts a hard limit on reuse.

Web Components are a standard JavaScript technology whose adoption has soared in recent years. Since it enables your components to work in any JavaScript code base , whether you are using frameworks/libraries like React, Angular, Vue, or vanilla JavaScript, you can use Web Components everywhere. Author Stephen Belovarich , Principal Software Development Engineer at Workday, unpacks practical ways to build real world apps using the latest evolution of the web spec. In Part 1 of the book , you learn the basics of Web Components and build some standard component building blocks.

Compared to other web development frameworks, Next.js has become very popular because of its support for a number of rendering strategies that result in highly performant frontend applications: By having the content readily available in the initial HTML document, less client-side rendering takes place. All the client has to do is hydrate the components and make them functional. The less dynamic content the client renders, the better the application's performance and SEO. Search engine bots like Googlebot can visit the application, immediately crawl (and understand) its content and rank it high on search engines. If you use Web Components to build your application's UI, then you don't need to worry about the breaking changes that third-party JavaScript frameworks/libraries notoriously cause (as a result of rapid development and release cycles). Your application performs equally as well as (or better than) applications that use these frameworks/libraries. Additionally, the low-level, native APIs of Web Components are based on an official W3 specification and let you develop encapsulated, modular and reusable components (represented as custom HTML elements).

Ever since the introduction of open source libraries and frameworks like React and Vue , the most popular approach for building user interfaces has been the composition of small, reusable components to create larger, more complex components and views. An often glossed over alternative that follows a similar paradigm is Web Components . As a collection of browser standards maintained by the WHATWG and W3C, Web Components lets you develop custom components, and use them anywhere in your application like regular HTML elements, with native browser APIs. It consists of three primary specifications that are implemented by all major browsers. Together, these specifications make self-contained components, each one encapsulating its own set of functionalities and structure: Third-party libraries and frameworks are known to frequently release new versions and introduce breaking changes. However, the lengthy, rigorous process of reviewing and approving changes to official specifications by the WHATWG and W3C results in far less breaking changes, which means less wasted development time. Using Web Components, components can extend from native HTML elements to augment their capabilities (i.e. clicking a table cell pops open a tooltip) while also retaining their accessibility characteristics. Commonly, Web Components can be found in applications built with Lit (successor of the deprecated Polymer library) or AMP . If we have to share components across different Web Components-based applications, then we need to be sure that these components can work standalone regardless of their environment.