Web components are a way to create custom, reusable elements for use in web pages and web applications. They allow developers to create their own HTML tags and use them in the same way as built-in elements like <div>
and <p>
. Stencil.js is a popular open-source tool that helps developers create web components with minimal setup and config. It’s a great tool for building design systems, as it allows for consistent and reusable components across an entire application.
Creating web components with Stencil is easy and straightforward. First, you need to install the Stencil CLI by running npm install -g @stencil/cli
in your terminal. After that, you can use the create
command to create a new project: npx create-stencil my-component
. This will create a new project in a folder called my-component
with all the necessary files and configs.
Let’s take an example of creating a reusable button component.
import { Component, h, Prop } from '@stencil/core'; @Component({ tag: 'my-button', styleUrl: 'my-button.css', shadow: true }) export class MyButton { @Prop() text: string; render() { return ( <button> <slot>{this.text}</slot> </button> ); } }
Here, we are creating a component with the tag name “my-button” and it uses the ‘my-button.css’ for styling. The <slot>
element is used to insert the text passed as a property.
One of the key benefits of using Stencil.js is that its syntax is familiar to developers who are already familiar with other frameworks such as Angular, React, and Vue. This makes it easy for developers to learn and use, even if they don’t have previous experience with web components. Stencil.js uses JSX for defining the template of the component, which is similar to the JSX used in React. This allows developers to use the same familiar syntax for both building web components and building the rest of their application. Additionally, the use of decorators in Stencil.js is similar to the decorators used in Angular, which makes it easy for developers who are already familiar with Angular to start using Stencil.js. This familiar syntax makes it easy for teams to start using Stencil.js without a steep learning curve, which can help to increase productivity and reduce the time required to build a design system
Once your component is set up, you can start creating your web component by defining a new class in the src/components
folder. The class should extend the Component
class provided by Stencil and include a render()
method that returns the HTML template of the component. You can use JSX syntax to define the template, which makes it easy to include dynamic data and event handlers.
To use your new web component, you’ll need to import it in your HTML file and add it to the DOM like any other HTML element.
<!-- using the new component --> <my-button text="Click me"></my-button>
You can also use the @Prop
decorator to define properties for your component and the @State
decorator for state variables. These properties and state can be passed in from the parent component and used in the component’s template.
One of the powerful feature of Stencil is its ability to use Web API’s like Shadow DOM, Custom Elements, and ES Modules, which makes it highly performant and also compatible with any framework or library. In addition, Stencil also provides a set of decorators, which makes it easy to handle lifecycle events, props, states and also makes it easy to handle events. This makes it easy to manage the behavior of your design system components, and also allows you to make changes to your design system without affecting other parts of your application.
Another great feature of Stencil is its ability to create highly optimized web components. When you build your component using the npm run build
command, Stencil automatically optimizes your code by removing unnecessary code, minifying the output, and bundling all the dependencies. This results in smaller and faster web components that can be easily integrated into any web page or application.
Creating optimized web components with Stencil can greatly improve the performance of your design system. One of the ways that Stencil optimizes your code is by using a technique called “tree shaking” during the build process. This means that it only includes the code that is actually used in the final bundle, and removes any unused code. This results in smaller, more efficient web components that can be easily integrated into any web page or application.
Another way that Stencil optimizes your web components is by using code splitting. This means that your code is divided into smaller chunks, which can be loaded on demand as needed. This improves the initial load time of your application, as the user only needs to load the code that is immediately needed, rather than downloading all the code at once. This also allows for better caching of the code, as the user only needs to download the code that has changed, rather than downloading all the code every time they visit the site.
In addition to these optimization techniques, Stencil also provides a set of performance metrics that you can use to measure the performance of your web components. This allows you to track the performance of your components over time and make adjustments as needed to improve the performance of your design system.
Building design systems with Stencil can bring many benefits to your development process.