Introduction to Stencil.js
Tags: webdev, javascript, tutorial, beginners
Published: 2023-03-24 15:41:08

Stencil.js is a web component compiler built by the Ionic framework team. It allows developers to create reusable web components. Stencil.js takes the best features of modern front-end frameworks and compiles them into standalone, framework-independent components. 

These components can be used in JavaScript frameworks such as React and Angular or without frameworks. This article provides information on how to get started with using Stencil.js.


## Why Use Stencil.js

There are several benefits to utilizing stencil.js. One of the main advantages of Stencil.js is that it is simple and easy to learn since it has a simple and intuitive syntax that makes it easy for developers to get started.

Stencil.js allows developers to create reusable components that can be used across multiple projects, saving time and effort in the development process. Stencil.js components can be used in various javascript frameworks like React.

Stencil.js also provides advanced features, such as asynchronous rendering, lazy loading, and optimized bundling out-of-the-box. This makes it an excellent choice for building high-performance web applications.


## How Does Stencil.js Work?

Stencil.js uses a component-based architecture, meaning that developers define UI components as separate, reusable pieces of code. These components can be used together to build a complete web application.

Stencil.js uses TypeScript, a statically typed language, to provide strong typing and improved code readability. Stencil also uses JSX and CSS to create high-quality components. 

Stencil.js supports modern JavaScript features, such as async/await, and can be easily integrated with other libraries and frameworks.


## Getting Started With Stencil.js

To start using Stencil.js, you must install the Stencil CLI and create a new project. The CLI provides a simple command-line interface for building Stencil.js projects.

 

To install the CLI, run the following command in your project’s directory on the terminal:

```bash
npm init stencil
```


While running the command, a prompt will display on your screen with options displaying the types of projects:

```bash
? Select a starter project.

Starters marked as [community] are developed by the Stencil Community,
rather than Ionic. For more information on the Stencil Community, please see
https://github.com/stencil-community » - Use arrow-keys. Return to submit.
>   component                Collection of web components that can be used anywhere
    app [community]          Minimal starter for building a Stencil app or website
    ionic-pwa [community]    Ionic PWA starter with tabs layout and routes
```


Based on the option you select, you can create reusable web components or a complete stencil.js application/website.

After selecting the type of project you wish to build, you give the project a name:

```bash
√ Project name ...stencil-project
? Confirm? » (Y/n)
```


After you confirm your choice, the CLI will create a stencil.js project with the project name you specified in the project’s directory. Then, change your directory to your project’s directory and install your required dependencies.

To install the dependencies, run the following command:

```bash
npm install
```

  

Once you have created a new project, you can start writing components. 


## Creating Your First Component

To create a stencil.js component, you create a new component folder within the `src/components` directory. Within that folder, generate your `.tsx` file. You create a `.tsx` file because stencil uses typescript and JSX to develop components.

You will create your stencil.js component in the `.tsx` file:

```jsx
import { Component, h } from "@stencil/core";

@Component({
    tag: 'my-component',
})

export class MyComponent{
  render() {
    return (
      <div>This is my first component</div>
    )
  }
}
```

In the code blocks above, you import the `Component` and `h` symbols from the `@stencil/core` module. The `Component` is a decorator used to define stencil components, and `h` is a utility function that creates virtual DOM elements. 

The component definition uses h to return a virtual div element with the text content "This is my first component.” The component is defined using the `@Component` decorator. 

The `@Component` decorator allows you to specify the component's tag name and any other component configuration options. The class, `MyComponent` exports the component definition. 

The render function returns JSX, which will render the component in the browser. After creating your component, you render it in your HTML file.

Like so: 

```html
<!DOCTYPE html>
<html dir="ltr" lang="en">
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=5.0" />
    <title>Stencil Project</title>
  </head>
  <body>
    <my-component></my-component>
  </body>
</html>
```


## Conclusion

Stencil.js is a powerful and flexible tool for building reusable UI components for the web. It provides a simple, easy-to-learn API and advanced features such as asynchronous rendering and lazy loading. Whether you are a seasoned front-end developer or just starting, Stencil.js is an excellent choice for building high-performance web applications.