react component to create filter list

filterlist.js

/** @jsx React.DOM */

var itemList = [
  'Apples',
  'Pie',
  'Brocooli',
  'Chicken',
  'Duck',
  'Eggs',
  'Fish',
  'Granola',
  'Hash Browns'
];

var FilteredList = React.createClass({
  filterList: function(event) {
    var updatedList = this.props.initialItems;
    updatedList = updatedList.filter(function(item) {
      return item.toLowerCase().indexOf(
        event.target.value.toLowerCase()
      ) !== -1;
    });
    this.setState({
      items: updatedList
    });
  },

  componentWillMount: function() {
    this.setState({
      items: this.props.initialItems
    });
  },

  render: function() {
    return (
      <div className="filter-list">
        <input type="text" placeholder="Search" onChange={this.filterList} />
        <List items={this.state.items} />
      </div>
    );
  }
});

var List = React.createClass({
  render: function() {
    return (
      <ul>
        {
          this.props.items.map(function(item) {
            return <li key={item}>{item}</li>
          })
        }
      </ul>
    );
  }
});

React.renderComponent(
  <FilteredList initialItems={itemList} />,
  document.getElementById('mount-point')
);