Getting Started
Last updated
Last updated
🏅One of the four nominated projects to the "Breakthrough of the year" category of Open Source Award in 2019
Hybrids is a UI library for creating web components with strong declarative and functional approach based on plain objects and pure functions.
The simplest definition — just plain objects and pure functions - no class
and this
syntax
No global lifecycle — independent properties with own simplified lifecycle methods
Composition over inheritance — easy re-use, merge or split property definitions
Super fast recalculation — built-in smart cache and change detection mechanisms
Templates without external tooling — template engine based on tagged template literals
Developer tools included — Hot module replacement support for a fast and pleasant development
Add the hybrids npm package to your application, or use unpkg.com/hybrids CDN for direct usage in the browser.
Then, import required features and define your custom element:
Finally, use your custom element in HTML document:
Click and play with
<simple-counter>
example:
If you target modern browsers you can use source code directly in the script tag:
Be aware, that this mode does not provide code minification and loads all required files in separate requests.
HMR works out of the box, but your bundler setup may require indication that your entry point supports it. For webpack
and parcel
add the following code to your entry point:
If your entry point imports files that do not support HMR, you can place the above snippet in a module where you define a custom element. (where define
method from the library is used).
There are some common patterns among JavaScript UI libraries like class syntax, a complex lifecycle or stateful architecture. What can we say about them?
Classes can be confusing, especially about how to use this
or super()
calls. They are also hard to compose. Multiple lifecycle callbacks have to be studied to understand very well. A stateful approach can open doors for difficult to maintain, imperative code. Is there any way out from all of those challenges?
After all, the class syntax in JavaScript is only sugar on top of the constructors and prototypes. Because of that, we can switch the component structure to a map of properties applied to the prototype of the custom element class constructor. Lifecycle callbacks can be minimized with smart change detection and cache mechanism. Moreover, they can be implemented independently in the property scope rather than globally in the component definition.
With all of that, the code may become simple to understand, and the code is written in a declarative way. Not yet sold? You can read more in the Core Concepts section of the project documentation.
The hybrids documentation is available at hybrids.js.org or in the docs path of the repository:
Core Concepts Series
Taste the Future with Functional Web Components (EN, ConFrontJS Conference)
Hybrids - Web Components with Simple and Functional API *(PL, WarsawJS Meetup #46)
<simple-counter> - a button with counter controlled by own state
<redux-counter> - Redux library for state management
<react-counter> - render factory and React library for rendering in shadow DOM
<lit-counter> - render factory and lit-html for rendering in shadow DOM
<app-todos> - todo list using parent factory for state management
<tab-group> - switching tabs using children factory
<async-user> - async data in the template
The library requires ES2015 APIs, Shadow DOM, Custom Elements, and Template specifications. You can use hybrids in all evergreen browsers without additional preparation.
The library test suite runs on IE11, but in near future only evergreen browsers will be supported starting from v5.0.0
release. However, if you still target obsolete or dead browsers (like IE11) you must add a list of required polyfills and shims.
Web Components
At first, add @webcomponents/webcomponentsjs
package on top of your project:
The polyfill package provides two modes in which you can use it (webcomponents-bundle.js
and webcomponents-loader.js
). Read more in the How to use section of the documentation.
Web components shims have some limitations. Especially, webcomponents/shadycss
approximates CSS scoping and CSS custom properties inheritance. Read more on the known issues and custom properties shim limitations pages.
Store
Additionally, the store feature requires a fix for broken implementation of the WeakMap
in IE11:
hybrids
is released under the MIT License.