The previous lesson introduced the React component lifecycle mounting and unmounting. In this lesson you will learn some simple uses for these hooks.
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Component Lifecycle: Mounting Uses</title>
<script src="http://fb.me/react-0.8.0.js"></script>
<script src="http://fb.me/JSXTransformer-0.8.0.js"></script>
<style>
body {
margin: 25px;
}
</style>
</head>
<body>
<button onClick="render()">Render</button>
<button onClick="unmount()">Unmount</button>
<hr />
<div id="panel"></div>
<script type="text/jsx">
/** @jsx React.DOM */
var APP =
React.createClass({
update:function(){
var newVal = this.props.val+1
this.setProps({val:newVal})
},
componentWillMount:function(){
this.setState({m:2});
if(this.props.val===0){
this.btnStyle = {'color':'red'}
}
},
render:function(){
console.log("hello world")
return <button
style={this.btnStyle}
onClick={this.update}>
{this.props.val*this.state.m}
</button>
},
componentDidMount:function(){
this.inc = setInterval(this.update,500)
},
componentWillUnmount:function(){
console.log("goodbye cruel world!")
clearInterval(this.inc)
},
}); window.render = function(){
React.renderComponent(
<APP val={0} />,
document.getElementById('panel'))
}
window.unmount = function(){
React.unmountComponentAtNode(document.getElementById('panel'))
}
</script>
</body>
</html>