react-redux-0.4.0.zip

react-redux ========================= Higher-order React components for [Redux](https://github.com/gaearon/redux). What you get from `react-redux` is for React. For React Native, import from `react-redux/native` instead. >**Note: There is a project called “redux-react” on NPM that is completely unrelated to the official bindings. This documentation (and any other official Redux documentation) is for `react-redux`.** - [Quick Start](#quick-start) - [API](#api) - [`connect`](#connect) - [`Provider`](#provider) ## Quick Start React bindings for Redux embrace the idea of [dividing “smart” and “dumb” components](https://medium.com/@dan_abramov/smart-and-dumb-components-7ca2f9a7c7d0). It is advisable that only top-level components of your app (such as route handlers, for example) are aware of Redux. Components below them should be “dumb” and receive all data via props.

	Location	Use React-Redux	To read data, they	To change data, they
“Smart” Components	Top level, route handlers	Yes	Subscribe to Redux state	Dispatch Redux actions
“Dumb” Components	Middle and leaf components	No	Read data from props	Invoke callbacks from props

### “Dumb” component is unaware of Redux Let’s say we have a `` “dumb” component with a number `counter` prop, and an `increment` function prop that it will call when user presses an “Increment” button: ```js import { Component } from 'react'; export default class Counter extends Component { render() { return ( {this.props.counter} ); } } ``` ### “Smart” component is `connect()`-ed to Redux Here’s how we hook it up to the Redux Store. We will use `connect()` function provided by `react-redux` to turn a “dumb” `Counter` into a smart component. With the current API, we’ll need to add an intermediate `CounterContainer` component, but we will soon make `connect` API more powerful so this won’t be required. The `connect()` function lets you specify *which exactly* state from the Redux store your component wants to track. This lets you subscribe on any level of granularity. Our `CounterContainer` that’s necessary to hook `Counter` up to a Redux store looks like this: (This will be much less verbose in the next versions.) ```js import { Component } from 'react'; import { connect } from 'react-redux'; // Assuming this is our “dumb” counter import Counter from '../components/Counter'; // Assuming these are Redux action creators import { increment } from './actionCreators'; function select(state) { // Which part of the Redux global state does our component want to receive as props? return { counter: state.counter }; } class CounterContainer extends Component { render() { // connect() call below will inject `dispatch` and // every key returned by `select` as props into our container: const { dispatch, counter } = this.props; // render our “dumb” component, hooking up state to data props // and using “dispatch action produced by this action creator” as callbacks. // this is a “bridge” between a Redux-aware world above and Redux-unaware world below. return ( dispatch(increment())} /> ); } } // Don't forget to actually use connect! export default connect(select)(CounterContainer); // You might have noticed that we used parens twice. // This is called partial applications, and it lets people // use ES7 decorator proposal syntax: // // @connect(select) // export default class CounterContainer { ... } // // Don’t forget decorators are experimental! And they // desugar to function calls anyway as example above demonstrates. ``` As you can see, action creators in Redux just return actions, but we need to manually “bind” them to the `dispatch` function for our Redux store. Why don’t we bind action creators to a store right away? This is because of the so-called “universal” apps that need to render on the server. They would have a different store instance for every request, so we don’t know the store instance during the definition! ### Binding many action creators Binding can get cumbersome, so Redux provides a `bindActionCreators` helper to turn many action creator methods into an object with methods called the same, but bound to a particular `dispatch` function: ```js import { Component } from 'react'; import { connect } from 'react-redux'; // A helper provided by Redux! import { bindActionCreators } from 'redux'; // Import many action creators as a single object (like `require('./actionCreators')` in CommonJS) import * as CounterActionCreators from './actionCreators'; import Counter from '../components/Counter'; function select(state) { return { counter: state.counter }; } class CounterContainer extends Component { render() { const { dispatch, counter } = this.props; // This time, we use `bindActionCreators` to bind many action creators // to a particular dispatch function from our Redux store. return ( ); } } // Don't forget to actually use connect! export default connect(select)(CounterContainer); ``` You can have many `connect()`-ed components in your app at any depth, and you can even nest them. It is however preferable that you try to only `connect()` top-level components such as route handlers, so the data flow in your application stays predictable. ### Injecting Redux store Finally, how do we actually hook it up to a Redux store? We need to create the store somewhere at the root of our component hierarchy. For client apps, the root component is a good place. For server rendering, you can do this in the request handler. The trick is to wrap the whole view hierarchy into `{() => ... }` where `Provider` is imported from `react-redux`. One gotcha is that **the child of `Provider` must be a function**. This is to work around an issue with how context (undocumented feature we have to rely on to pass Redux data to components below) works in React 0.13. In React 0.14, you will be able to put your view hierarchy in `` without wrapping it into a function. ```js import { Component } from 'react'; import { Provider } from 'react-redux'; class App extends Component { render() { // ... } } const targetEl = document.getElementById('root'); React.render(( {() => } ), targetEl); // or, if you use React Router 0.13, // Router.run(routes, Router.HistoryLocation, (Handler) => { // React.render( // // {() => } // , // targetEl // ); // }); // or, if you use React Router 1.0, // React.render( // // {() => ...} // , // targetEl // ); ``` ## API ### `connect` ```js export default connect(select)(MyComponent); ``` Returns a component class that injects the Redux Store’s `dispatch` as a prop into `Component` so it can dispatch Redux actions. The returned component also subscribes to the updates of Redux store. Any time the state changes, it calls the `select` function passed to it. The selector function takes a single argument of the entire Redux store’s state and returns an object to be pass