Files
react/packages/react-reconciler
Sebastian MarkbågeandGitHub 96e5d57d2f Move some files out of /shared and rename to upper case (#18363)
* Rename lower case isomorphic default exports modules to upper case named exports

We're somewhat inconsistent here between e.g. ReactLazy and memo.

Let's pick one.

This also moves the responder, fundamental, scope creators from shared
since they're isomorphic and same as the other creators.

* Move some files that are specific to the react-reconciler from shared

Individual renderers are allowed to deep require into the reconciler.

* Move files specific to react-dom from shared

react-interactions is right now dom specific (it wasn't before) so we can
type check it together with other dom stuff. Avoids the need for
a shared ReactDOMTypes to be checked by RN for example.

* Move ReactWorkTags to the reconciler

* Move createPortal to export from reconciler

Otherwise Noop can't access it since it's not allowed deep requires.
2020-03-21 15:22:01 -07:00
..

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 we’ll 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 we’ll try to help!