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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <head>
	<script src="https://unpkg.com/react@15/dist/react.js"></script>
<script src="https://unpkg.com/react-dom@15/dist/react-dom.js"></script>
</head>
<body>
	<div id="app"></div>
</body>
            
          
!
            
              .updated {
	border:1px solid green;
	padding:3px;
}
            
          
!
            
              // stateless component
function Username(props) {
	return(
		<p onClick={() => props.nameClickedHandler(props.name)}>{props.name}</p>
	)
}

class App extends React.Component {
	constructor(props) {
		super(props);
		
		this.state = {
			name: props.name,
			elements: [],
			message:""
		}
	}
	userWasClicked(name) {
		alert("name clicked: " + name);
	}
	addElement() {
		// On COPIE toujours le précédent élement de l'état qu'on va changer
		const oldElements = this.state.elements;
		
		this.setState({
			elements: oldElements.concat(oldElements.length + 1) // concat retourne un nouveau tableau, pas de push ici !!!
		});
	}
	changeName() {
		//this.state.name = 'Peter'; // NE MARCHE PAS !!!
		this.setState({
			name: 'Peter'
		}); 
	}
	changeInputMessage(event) {
		console.log("value = " + event.target.value);
		this.setState({
			message: event.target.value
		});
	}
	render() {
		let updateParagraph = '';
		let paragraphClass = 'updated';
		if(this.props.name !== this.state.name) {
			updateParagraph = <p className={paragraphClass}>Le nom a été modifié!</p>
		}
		let list = this.state.elements.map(
			(el) => {
				const liStyle = {
					color: (el %2) ? 'red' : 'green'
				}
				return <li key={el} style={liStyle}>{el}</li>
			}
		); 
		
		return(
			<div>
				<Username name="Michel Buffa" nameClickedHandler={this.userWasClicked}/>
				<Username name="PeterSander" nameClickedHandler={this.userWasClicked}/>
				
				
				<p className={paragraphClass}>{this.state.name}</p>
				<button onClick={(evt) => this.changeName(evt)}>Change the name v2 (better...)</button>
				<button onClick={() => this.addElement()}>Ajouter élement</button>
				{updateParagraph}
				<p>Liste des éléments:</p>
				<ul>
					{list}
				</ul>
				<label>Tapez quelque chose:
					<input 
					type="text" 
					value={this.state.message}
					onChange={this.changeInputMessage.bind(this)}
					/> 
				</label>
				<p>Vous avez saisi: {this.state.message}</p>
			</div>
		);
	}
}

ReactDOM.render(<App name="Michel"/>, document.querySelector("#app"));


            
          
!
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