Files
react/packages/react-reconciler
Laura buns b43eec7eaa Replace wrap-warning-with-env-check with an eslint plugin (#17540)
* Replace Babel plugin with an ESLint plugin

* Fix ESLint rule violations

* Move shared conditions higher

* Test formatting nits

* Tweak ESLint rule

* Bugfix: inside else branch, 'if' tests are not satisfactory

* Use a stricter check for exactly if (__DEV__)

This makes it easier to see what's going on and matches dominant style in the codebase.

* Fix remaining files after stricter check
2019-12-06 18:25:54 +00:00
..
2019-11-14 16:02:18 -08:00

react-reconciler

This is an experimental package for creating custom React renderers.

Its API is not as stable as that of React, React Native, or React DOM, and does not follow the common versioning scheme.

Use it at your own risk.

API

const Reconciler = require('react-reconciler');

const HostConfig = {
  // You'll need to implement some methods here.
  // See below for more information and examples.
};

const MyRenderer = Reconciler(HostConfig);

const RendererPublicAPI = {
  render(element, container, callback) {
    // Call MyRenderer.updateContainer() to schedule changes on the roots.
    // See ReactDOM, React Native, or React ART for practical examples.
  }
};

module.exports = RendererPublicAPI;

Practical Examples

A "host config" is an object that you need to provide, and that describes how to make something happen in the "host" environment (e.g. DOM, canvas, console, or whatever your rendering target is). It looks like this:

const HostConfig = {
  createInstance(type, props) {
    // e.g. DOM renderer returns a DOM node
  },
  // ...
  supportsMutation: true, // it works by mutating nodes
  appendChild(parent, child) {
    // e.g. DOM renderer would call .appendChild() here
  },
  // ...
};

For an introduction to writing a very simple custom renderer, check out this article series:

The full list of supported methods can be found here. For their signatures, we recommend looking at specific examples below.

The React repository includes several renderers. Each of them has its own host config.

The examples in the React repository are declared a bit differently than a third-party renderer would be. In particular, the HostConfig object mentioned above is never explicitly declared, and instead is a module in our code. However, its exports correspond directly to properties on a HostConfig object you'd need to declare in your code:

If these links break please file an issue and well fix them. They intentionally link to the latest versions since the API is still evolving. If you have more questions please file an issue and well try to help!