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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.

HTML

            
              <div id="container"></div>
            
          
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CSS

            
              .btn {
  position: absolute;
  transition: transform 2000ms;
  background-color: red;
  width: 50px;
  height: 50px;
  line-height: 50px;
  top: 0;
  left: 0;
  padding: 0;
}
            
          
!

JS

            
              // Child component that takes a numeric ID (for ease of tracking). 
// Render a simple button having the supplied ID as a label.
// Log to the console when it's mounted and unmounted from the DOM.
class Child extends React.Component {
  componentDidMount () { 
    console.log('Child ' + this.props.id + ' has been mounted')
  }
  componentWillUnmount() {
    console.log('Child ' + this.props.id + ' has been unmounted')
  }
  render() {
    const {id, x, y} = this.props;
    const style = {
      transform: `translateX(${x}px) translateY(${y}px)`,
    }
    return (
      <div className='btn btn-default' style={style}>{this.props.id}</div>
    )
  }
}
Child.propTypes = {
  id: React.PropTypes.number,
  x: React.PropTypes.number,
  y: React.PropTypes.number,
}

// View1 and View2 React functional components. Theyare identical from a markup standpoint. 
// The point of having separate functions is to test out the mounting/unmounting behavior
// of React.
// `View1` and `View2` are capitalized so that React knows that they are
// user-defined components instead of built-in components.
function View1() {
  return (
    <div>
      <Child id={1} key='child-1' x={20} y={0}/> 
      <Child id={2} key='child-2' x={200} y={0}/>
    </div>
  )
}
function View2() {
  return (
    <div>
      <Child id={1} key='child-1' x={60} y ={0}/> 
      <Child id={2} key='child-2' x={120} y={0}/>
    </div>
  )        
}

// A very simple Container that will first show view 1, then wait for one second and switch to view 2.
// It also logs out useful lifecycle messages.
class Container extends React.Component {   
  constructor() {
    super()
    this.state = {
      viewIndex: 1
    }
  }
  componentDidMount() {
    console.log('Container mounted')
    console.log('Will change viewIndex to 2 in one second.')
    setTimeout(() => {
      this.setState({viewIndex: 2})
    }, 1000)
  }
  componentDidUpdate() {
    console.log("Container's state has been updated to " + this.state.viewIndex + " and finished re-render.")
  }
  render() {
    const {viewIndex} = this.state;
    if (viewIndex === 1) {
      return View1()
    } else {
      return View2()
    }
  }
}

ReactDOM.render(<Container/>, document.getElementById('container'))
            
          
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999px

Console