We’re happy to announce our first release candidate for React 0.14! We gave you a [sneak peek in July](/react/blog/2015/07/03/react-v0.14-beta-1.html) at the upcoming changes but we’ve now stabilized the release more and we’d love for you to try it out before we release the final version.
We’re happy to announce the release of React 0.14 today! This release has a few major changes, primarily designed to simplify the code you write every day and to better support environments like React Native.
Let us know if you run into any problems by filing issues on our [GitHub repo](https://github.com/facebook/react).
If you tried the release candidate, thank you – your support is invaluable and we've fixed a few bugs that you reported.
As with all of our releases, we consider this version to be stable enough to use in production and recommend that you upgrade in order to take advantage of our latest improvements.
## Upgrade Guide
Like always, we have a few breaking changes in this release. We know changes can be painful (the Facebook codebase has over 15,000 React components), so we always try to make changes gradually in order to minimize the pain.
If your code is free of warnings when running under React 0.13, upgrading should be easy. We have two new small breaking changes that didn't give a warning in 0.13 (see below). Every new change in 0.14, including the major changes below, is introduced with a runtime warning and will work as before until 0.15, so you don't have to worry about your app breaking with this upgrade.
See the changelog below for more details.
## Installation
We recommend using React from `npm` and using a tool like browserify or webpack to build your code into a single package:
We recommend using React from `npm` and using a tool like browserify or webpack to build your code into a single bundle. To install the two packages:
* `npm install --save react@0.14.0-rc1`
* `npm install --save react-dom@0.14.0-rc1`
* `npm install --save react react-dom`
Remember that by default, React runs extra checks and provides helpful warnings in development mode. When deploying your app, set the `NODE_ENV` environment variable to `production` to use the production build of React which does not include the development warnings and runs significantly faster.
If you can’t use `npm` yet, we also provide pre-built browser builds for your convenience:
If you can’t use `npm` yet, we provide pre-built browser builds for your convenience, which are also available in the `react` package on bower.
* **React**
Dev build with warnings: <https://fb.me/react-0.14.0-rc1.js>
Minified build for production: <https://fb.me/react-0.14.0-rc1.min.js>
Dev build with warnings: <https://fb.me/react-0.14.0.js>
Minified build for production: <https://fb.me/react-0.14.0.min.js>
* **React with Add-Ons**
Dev build with warnings: <https://fb.me/react-with-addons-0.14.0-rc1.js>
Minified build for production: <https://fb.me/react-with-addons-0.14.0-rc1.min.js>
Dev build with warnings: <https://fb.me/react-with-addons-0.14.0.js>
Minified build for production: <https://fb.me/react-with-addons-0.14.0.min.js>
* **React DOM** (include React in the page before React DOM)
Dev build with warnings: <https://fb.me/react-dom-0.14.0-rc1.js>
Minified build for production: <https://fb.me/react-dom-0.14.0-rc1.min.js>
These builds are also available in the `react` package on bower.
Dev build with warnings: <https://fb.me/react-dom-0.14.0.js>
Minified build for production: <https://fb.me/react-dom-0.14.0.min.js>
## Changelog
@ -57,15 +64,26 @@ These builds are also available in the `react` package on bower.
ReactDOM.render(<MyComponent/>, node);
```
We’ve published the [automated codemod script](https://github.com/facebook/react/blob/master/packages/react-codemod/README.md) we used at Facebook to help you with this transition.
The old names will continue to work with a warning until 0.15 is released, and we’ve published the [automated codemod script](https://github.com/facebook/react/blob/master/packages/react-codemod/README.md) we used at Facebook to help you with this transition.
The add-ons have moved to separate packages as well: `react-addons-clone-with-props`, `react-addons-create-fragment`, `react-addons-css-transition-group`, `react-addons-linked-state-mixin`, `react-addons-perf`, `react-addons-pure-render-mixin`, `react-addons-shallow-compare`, `react-addons-test-utils`, `react-addons-transition-group`, and `react-addons-update`, plus `ReactDOM.unstable_batchedUpdates` in `react-dom`.
The add-ons have moved to separate packages as well:
- `react-addons-clone-with-props`
- `react-addons-create-fragment`
- `react-addons-css-transition-group`
- `react-addons-linked-state-mixin`
- `react-addons-perf`
- `react-addons-pure-render-mixin`
- `react-addons-shallow-compare`
- `react-addons-test-utils`
- `react-addons-transition-group`
- `react-addons-update`
- `ReactDOM.unstable_batchedUpdates` in `react-dom`.
For now, please use matching versions of `react` and `react-dom` in your apps to avoid versioning problems.
For now, please use matching versions of `react` and `react-dom`(and the add-ons, if you use them) in your apps to avoid versioning problems.
- #### DOM node refs
The other big change we’re making in this release is exposing refs to DOM components as the DOM node itself. That means: we looked at what you can do with a `ref` to a React DOM component and realized that the only useful thing you can do with it is call `this.refs.giraffe.getDOMNode()` to get the underlying DOM node. In this release, `this.refs.giraffe`_is_ the actual DOM node. **Note that refs to custom (user-defined) components work exactly as before; only the built-in DOM components are affected by this change.**
The other big change we’re making in this release is exposing refs to DOM components as the DOM node itself. That means: we looked at what you can do with a `ref` to a React DOM component and realized that the only useful thing you can do with it is call `this.refs.giraffe.getDOMNode()` to get the underlying DOM node. Starting with this release, `this.refs.giraffe`_is_ the actual DOM node. **Note that refs to custom (user-defined) components work exactly as before; only the built-in DOM components are affected by this change.**
```js
var Zoo = React.createClass({
@ -80,14 +98,16 @@ These builds are also available in the `react` package on bower.
});
```
This change also applies to the return result of `ReactDOM.render` when passing a DOM node as the top component. As with refs, this change does not affect custom components. With these changes, we’re deprecating `.getDOMNode()` and replacing it with `ReactDOM.findDOMNode` (see below).
This change also applies to the return result of `ReactDOM.render` when passing a DOM node as the top component. As with refs, this change does not affect custom components.
With this change, we’re deprecating `.getDOMNode()` and replacing it with `ReactDOM.findDOMNode` (see below). If your components are currently using `.getDOMNode()`, they will continue to work with a warning until 0.15.
- #### Stateless function components
- #### Stateless functional components
In idiomatic React code, most of the components you write will be stateless, simply composing other components. We’re introducing a new, simpler syntax for these components where you can take `props` as an argument and return the element you want to render:
```js
// Using an ES2015 (ES6) arrow function:
// A functional component using an ES2015 (ES6) arrow function:
var Aquarium = (props) => {
var fish = getFish(props.species);
return <Tank>{fish}</Tank>;
@ -103,6 +123,8 @@ These builds are also available in the `react` package on bower.
// Then use: <Aquariumspecies="rainbowfish"/>
```
These components behave just like a React class with only a `render` method defined. Since no component instance is created for a functional component, any `ref` added to one will evaluate to `null`. Functional components do not have lifecycle methods, but you can set `.propTypes` and `.defaultProps` as properties on the function.
This pattern is designed to encourage the creation of these simple components that should comprise large portions of your apps. In the future, we’ll also be able to make performance optimizations specific to these components by avoiding unnecessary checks and memory allocations.
- #### Deprecation of react-tools
@ -120,7 +142,10 @@ These builds are also available in the `react` package on bower.
### Breaking changes
As always, we have a few breaking changes in this release. Whenever we make large changes, we warn for at least one release so you have time to update your code. The Facebook codebase has over 15,000 React components, so on the React team, we always try to minimize the pain of breaking changes.
In almost all cases, we change our APIs gradually and warn for at least one release to give you time to clean up your code. These two breaking changes did not have a warning in 0.13 but should be easy to find and clean up:
- `React.initializeTouchEvents` is no longer necessary and has been removed completely. Touch events now work automatically.
- Add-Ons: Due to the DOM node refs change mentioned above, `TestUtils.findAllInRenderedTree` and related helpers are no longer able to take a DOM component, only a custom component.
These three breaking changes had a warning in 0.13, so you shouldn’t have to do anything if your code is already free of warnings:
@ -128,16 +153,13 @@ These three breaking changes had a warning in 0.13, so you shouldn’t have to d
- Plain objects are no longer supported as React children; arrays should be used instead. You can use the [`createFragment`](/react/docs/create-fragment.html) helper to migrate, which now returns an array.
- Add-Ons: `classSet` has been removed. Use [classnames](https://github.com/JedWatson/classnames) instead.
And these two changes did not warn in 0.13 but should be easy to find and clean up:
- `React.initializeTouchEvents` is no longer necessary and has been removed completely. Touch events now work automatically.
- Add-Ons: Due to the DOM node refs change mentioned above, `TestUtils.findAllInRenderedTree` and related helpers are no longer able to take a DOM component, only a custom component.
### New deprecations, introduced with a warning
Each of these changes will continue to work as before with a new warning until the release of 0.15 so you can upgrade your code gradually.
- Due to the DOM node refs change mentioned above, `this.getDOMNode()` is now deprecated and `ReactDOM.findDOMNode(this)` can be used instead. Note that in most cases, calling `findDOMNode` is now unnecessary – see the example above in the “DOM node refs” section.
If you have a large codebase, you can use our [automated codemod script](https://github.com/facebook/react/blob/master/packages/react-codemod/README.md) to change your code automatically.
With each returned DOM node, we've added a `getDOMNode` method for backwards compatibility that will work with a warning until 0.15. If you have a large codebase, you can use our [automated codemod script](https://github.com/facebook/react/blob/master/packages/react-codemod/README.md) to change your code automatically.
- `setProps` and `replaceProps` are now deprecated. Instead, call ReactDOM.render again at the top level with the new props.
- ES6 component classes must now extend `React.Component` in order to enable stateless function components. The [ES3 module pattern](/react/blog/2015/01/27/react-v0.13.0-beta-1.html#other-languages) will continue to work.
Ben Alpert
10 years ago