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freeCodeCamp/curriculum/challenges/russian/03-front-end-libraries/react-and-redux/use-provider-to-connect-redux-to-react.russian.md

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---
id: 5a24c314108439a4d4036144
title: Use Provider to Connect Redux to React
challengeType: 6
isRequired: false
forumTopicId: 301435
localeTitle: Использовать Провайдер для подключения Redux к действию
---
## Description
<section id='description'>
В последней задаче вы создали хранилище Redux для обработки массива сообщений и создали действие для добавления новых сообщений. Следующим шагом будет предоставление доступа React к хранилищу Redux и действия, необходимые для отправки обновлений. React Redux предоставляет пакет <code>react-redux</code> для выполнения этих задач. React Redux предоставляет небольшой API с двумя ключевыми функциями: <code>Provider</code> и <code>connect</code> . Другая проблема <code>connect</code> . <code>Provider</code> - это оболочка из React Redux, которая обертывает ваше приложение React. Затем этот обертку позволяет вам получить доступ к функциям <code>store</code> Redux и функции <code>dispatch</code> во всем дереве компонентов. <code>Provider</code> берет два реквизита, магазин Redux и дочерние компоненты вашего приложения. Определение <code>Provider</code> для компонента приложения может выглядеть так: <blockquote> &lt;Магазин-провайдер = {store}&gt; <br> &lt;Приложение /&gt; <br> &lt;/ Provider&gt; </blockquote>
</section>
## Instructions
<section id='instructions'>
The code editor now shows all your Redux and React code from the past several challenges. It includes the Redux store, actions, and the <code>DisplayMessages</code> component. The only new piece is the <code>AppWrapper</code> component at the bottom. Use this top level component to render the <code>Provider</code> from <code>ReactRedux</code>, and pass the Redux store as a prop. Then render the <code>DisplayMessages</code> component as a child. Once you are finished, you should see your React component rendered to the page.
<strong>Note:</strong>&nbsp;React Redux is available as a global variable here, so you can access the Provider with dot notation. The code in the editor takes advantage of this and sets it to a constant <code>Provider</code> for you to use in the <code>AppWrapper</code> render method.
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: The <code>AppWrapper</code> should render.
testString: assert((function() { const mockedComponent = Enzyme.mount(React.createElement(AppWrapper)); return mockedComponent.find('AppWrapper').length === 1; })());
- text: The <code>Provider</code> wrapper component should have a prop of <code>store</code> passed to it, equal to the Redux store.
testString: getUserInput => assert((function() { const mockedComponent = Enzyme.mount(React.createElement(AppWrapper)); return getUserInput('index').replace(/\s/g,'').includes('<Providerstore={store}>'); })());
- text: <code>DisplayMessages</code> should render as a child of <code>AppWrapper</code>.
testString: assert((function() { const mockedComponent = Enzyme.mount(React.createElement(AppWrapper)); return mockedComponent.find('AppWrapper').find('DisplayMessages').length === 1; })());
- text: The <code>DisplayMessages</code> component should render an h2, input, button, and <code>ul</code> element.
testString: assert((function() { const mockedComponent = Enzyme.mount(React.createElement(AppWrapper)); return mockedComponent.find('div').length === 1 && mockedComponent.find('h2').length === 1 && mockedComponent.find('button').length === 1 && mockedComponent.find('ul').length === 1; })());
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='jsx-seed'>
```jsx
// Redux Code:
const ADD = 'ADD';
const addMessage = (message) => {
return {
type: ADD,
message
}
};
const messageReducer = (state = [], action) => {
switch (action.type) {
case ADD:
return [
...state,
action.message
];
default:
return state;
}
};
const store = Redux.createStore(messageReducer);
// React Code:
class DisplayMessages extends React.Component {
constructor(props) {
super(props);
this.state = {
input: '',
messages: []
}
this.handleChange = this.handleChange.bind(this);
this.submitMessage = this.submitMessage.bind(this);
}
handleChange(event) {
this.setState({
input: event.target.value
});
}
submitMessage() {
const currentMessage = this.state.input;
this.setState({
input: '',
messages: this.state.messages.concat(currentMessage)
});
}
render() {
return (
<div>
<h2>Type in a new Message:</h2>
<input
value={this.state.input}
onChange={this.handleChange}/><br/>
<button onClick={this.submitMessage}>Submit</button>
<ul>
{this.state.messages.map( (message, idx) => {
return (
<li key={idx}>{message}</li>
)
})
}
</ul>
</div>
);
}
};
const Provider = ReactRedux.Provider;
class AppWrapper extends React.Component {
// render the Provider here
// change code above this line
};
```
</div>
### After Tests
<div id='jsx-teardown'>
```jsx
ReactDOM.render(<AppWrapper />, document.getElementById('root'))
```
</div>
</section>
## Solution
<section id='solution'>
```jsx
// Redux Code:
const ADD = 'ADD';
const addMessage = (message) => {
return {
type: ADD,
message
}
};
const messageReducer = (state = [], action) => {
switch (action.type) {
case ADD:
return [
...state,
action.message
];
default:
return state;
}
};
const store = Redux.createStore(messageReducer);
// React Code:
class DisplayMessages extends React.Component {
constructor(props) {
super(props);
this.state = {
input: '',
messages: []
}
this.handleChange = this.handleChange.bind(this);
this.submitMessage = this.submitMessage.bind(this);
}
handleChange(event) {
this.setState({
input: event.target.value
});
}
submitMessage() {
const currentMessage = this.state.input;
this.setState({
input: '',
messages: this.state.messages.concat(currentMessage)
});
}
render() {
return (
<div>
<h2>Type in a new Message:</h2>
<input
value={this.state.input}
onChange={this.handleChange}/><br/>
<button onClick={this.submitMessage}>Submit</button>
<ul>
{this.state.messages.map( (message, idx) => {
return (
<li key={idx}>{message}</li>
)
})
}
</ul>
</div>
);
}
};
const Provider = ReactRedux.Provider;
class AppWrapper extends React.Component {
// change code below this line
render() {
return (
<Provider store = {store}>
<DisplayMessages/>
</Provider>
);
}
// change code above this line
};
```
</section>