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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.

            
              <div id="react-mount">
<header>
<h1>Animating React State Changes</h1>
<header>
</div>
            
          
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              [role="button"],
input[type="submit"],
input[type="reset"],
input[type="button"],
button {
    -webkit-box-sizing: content-box;
       -moz-box-sizing: content-box;
            box-sizing: content-box;
}

/* Reset `button` and button-style `input` default styles */
input[type="submit"],
input[type="reset"],
input[type="button"],
button {
    background: none;
    border: 0;
    color: inherit;
    /* cursor: default; */
    font: inherit;
    line-height: normal;
    overflow: visible;
    padding: 0;
    -webkit-appearance: button; /* for input */
    -webkit-user-select: none; /* for button */
       -moz-user-select: none;
        -ms-user-select: none;
}
input::-moz-focus-inner,
button::-moz-focus-inner {
    border: 0;
    padding: 0;
}

header {
  width: 100%;
  height: 70px;
  line-height: 70px;
  display: flex;
  flex-direction: row;
  border-bottom: 1px solid rgb(215,215,215);
  box-sizing: border-box;
  padding: 0 20px;
}

header h1 {
  font-size: 24px;
  display: inline;
  vertical-align: middle;
  flex: 1;
  margin: 0;
  padding: 0;
}

header .buttons {
  align-self: flex-end;
  flex: 1;
  text-align: right;
}

header .buttons button {
  display: inline-block;
  border: 1px solid steelblue;
  border-radius: 3px;
  padding: 10px 15px;
  color: steelblue;
  
  &:hover {
    background: steelblue;
    color: white;
  }
}

.empty-state {
  margin-top: 200px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.empty-state h1 {
  color: steelblue;
}

.empty-state p {
  position: relative;
  display: block;
  width: 200px;
  height: 35px;
  line-height: 35px;
  padding: 10px;
  border-radius: 35px;
  color: rgb(100,100,100);
  text-align: center;
  background: lightgray;
  
  &:before {
    content: '';
    position: absolute;
    top: -12px;
    left: 50%;
    margin-left: -12px;
    display: block;
    width: 0;
    height: 0;
    border-bottom: 12px solid lightgray;
    border-left: 12px solid transparent;
    border-right: 12px solid transparent;
  }
}

.list-container {
  padding-left: 20px;
}

.list-container {
  h1,h2,h3,h4,h5 {
    margin: 0;
  }
}

.list-container li {
  display: flex;
  flex: 4;
  flex-direction: row;
  padding: 20px 30px;
  margin-bottom: 10px;
  background-color: white;
  border-bottom: 2px dotted rgb(215,215,215);
  box-sizing: border-box;
  
  &:last-child {
    margin-bottom: none;
  }
}

.list {
  margin: 10px auto 0 auto;
  padding: 0;
}

.list-badge {
  align-self: flex-start;
  display: block;
  width: 15px;
  height: 18px;
  margin-right: 20px;
  border: 1px dotted steelblue;
  color: steelblue;
  text-align: center;
  padding: 15px 8px;
}

.list-article-summary {
  flex: 2;
}

.list-title {
  color: #596673;
  font-weight: 300;
}

.list-author {
  color: #C1C1C1;
}

.list-post-date {
  color: #C1C1C1;
  align-self: center;
}

.list-close {
  margin-left: 20px;
  align-self: center;
  color: #C1C1C1;
  
  &:hover {
    color: crimson;
    cursor: pointer;
  }
}
            
          
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              var data = [
  {
    'key': 1,
    'title': 'An example article',
    'author': 'Chris Macrae',
    'time': 1455660206777
  },
  {
    'key': 2,
    'title': 'The truth about animated lists...',
    'author': 'Chris Macrae',
    'time': 1455660206777
  },
  {
    'key': 3,
    'title': 'Why I watched the Lion King 542 times as a child',
    'author': 'Chris Macrae',
    'time': 1455660206777
  },
  {
    'key': 4,
    'title': 'Daffy Duck laughing on repeat for 100 hrs',
    'author': 'Chris Macrae',
    'time': 1455660206777
  },
  {
    'key': 5,
    'title': '01101000 01100101 01101100 01101100 01101111',
    'author': 'Chris Macrae',
    'time': 1455660206777
  },
];

var ListContainer = React.createClass({
  getInitialState: function() {
    return {data: this.props.data};
  },
  render: function() {
    return (
      <div>
        <header>
          <h1>An animated react list</h1>
          <div className="buttons">
            <button className="data-toggle" onClick={this.mixItUp}>Mix it up!</button>
          </div>
        </header>
        <div className="list-container">
          <List items={this.state.data} ripItUp={this.ripItUp} resetIt={this.resetIt} />
        </div>
     </div>
    )
  },
  mixItUp: function() {
    var array = this.state.data;
    var currentIndex = array.length, temporaryValue, randomIndex;

    // While there remain elements to shuffle...
    while (0 !== currentIndex) {

      // Pick a remaining element...
      randomIndex = Math.floor(Math.random() * currentIndex);
      currentIndex -= 1;

      // And swap it with the current element.
      temporaryValue = array[currentIndex];
      array[currentIndex] = array[randomIndex];
      array[randomIndex] = temporaryValue;
    }

    this.setState({data: array});
  },
  ripItUp: function(key) {
    var array = this.state.data;
    if(!key) return;
    var ripItUpKey;
    array.forEach(function(item, index) {
      if(item.key === key) {
        ripItUpKey = index;
      }
    });

    if(ripItUpKey !== undefined) {
      array.splice(ripItUpKey, 1);
      this.setState({data: array});
    }
  },
  resetIt: function() {
    console.log(data);
    console.log(this.props.data);
    this.setState({data: data});
  }
})

var List = React.createClass({
  getInitialState: function() {
    return {};
  },
  componentWillMount: function() {
    this.setState({items: this.props.items});
  },
  render: function() {
    if(this.props.items.length === 0) {
      return(
        <div className="empty-state">
          <h1>щ(ಥДಥщ)</h1>
          <p class="caption"><em>I'm so empty and alone</em></p>
        </div>
      )
    }
    return(
      <ul className="list">
       {this.props.items.map(this.handleItemRender)}
      </ul>
    )
  },
  handleItemRender: function(item, index) {
    var postDate = moment(item.post_date).fromNow();
    return(
      <ListElement title={item.title} author={item.author} postDate={postDate} id={item.key} ref={item.key} key={item.key} ripItUp={this.props.ripItUp} />
    );
  },
  componentWillReceiveProps: function(nextProps) {
    var component = this;
    
    if(this.props.items.length > 0) {
      var newState = this.props.items.reduce(function(state, child) {
        if(!child.key) return state;
        var currentState = component.state;
        var domNode = ReactDOM.findDOMNode(component.refs[child.key]);
        var boundingBox = domNode.getBoundingClientRect();

        currentState[child.key] = boundingBox;
        currentState.items = component.props.items;

        return currentState;
      });

      this.setState(newState);
    }
  },
  componentWillUpdate: function(nextProps, nextState) {
    var component = this;
    var newKeys = [];
    var areDestroyed = [];
    
    nextProps.items.forEach(function(newProp) {
      newKeys.push(newProp.key);
    });
    
    this.state.items.forEach(function(oldProp) {
      if(newKeys.indexOf(oldProp.key) == -1) {
      }  
    });
  },
  componentDidUpdate: function(previousProps) {
    if(!this.state) return;
    
    var component = this;
    var areDestroyed = [];
    var doNeedAnimation = [];
    
    previousProps.items.forEach(function(item) {
      if(component.doesNeedAnimation(item) === 0) {
        doNeedAnimation.push(item);
      }
    });
    
    doNeedAnimation.forEach(this.animateAndTransform.bind(this));
  },
  animateAndDestroy: function(child, n) {
    var domNode = ReactDOM.findDOMNode(this.refs[child.key]);
    
    requestAnimaytionFrame(function() {
      requestAnimationFrame(function() {
        domNode.style.opacity = "0";
        domNode.style.transform = "scale(2)"
      });
    });
  },
  animateAndTransform: function(child, n) {
    var domNode = ReactDOM.findDOMNode(this.refs[child.key]);
    
    var [dX, dY] = this.getPositionDelta(domNode, child.key);
    
    requestAnimationFrame(function(){
      domNode.style.transition = 'transform 0s';
      domNode.style.transform = 'translate('+ dX + 'px, ' + dY + 'px)';
      requestAnimationFrame(function() {
        domNode.style.transform  = '';
        domNode.style.transition = 'transform 400ms';
      })
    });
  },
  doesNeedAnimation: function(child) {
    var isNotMovable = !child.key;
    var isNew = !this.state[child.key];
    var isDestroyed = !this.refs[child.key];
    
    if(isDestroyed) return 2;
    if(isNotMovable || isNew) return;
    
    var domNode = ReactDOM.findDOMNode(this.refs[child.key]);
    var [dX, dY] = this.getPositionDelta(domNode, child.key);
    var isStationary = dX === 0 && dY === 0;

    return (isStationary === true) ? 1 : 0;
  },
  getPositionDelta: function(domNode, key) {
    var newBox = domNode.getBoundingClientRect();
    var oldBox = this.state[key];
    
    return [
      oldBox.left - newBox.left,
      oldBox.top - newBox.top
    ];
  },
  
})

var ListElement = React.createClass({
  render: function() {
    return (
      <li>
        <span className="list-badge">{this.props.id}</span>
        <span className="list-article-summary">
          <h2 className="list-title">{this.props.title}</h2>
          <span className="list-author">{this.props.author}</span>
        </span>
        <span className="list-post-date">Posted {this.props.postDate}</span>
        <span className="list-close" onClick={this.props.ripItUp.bind(null, this.props.id)}>✕</span>
      </li>
    );
  },
})

React.render( 
  <ListContainer data={data} />,
  document.querySelector('#react-mount')
);
            
          
!
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