title: Each child in an array or iterator should have a unique "key" prop.
body: <p>I am getting error:</p>
  
  <p>Warning: Each child in an array or iterator should have a unique "key" prop.
  Can someone please help me where i have to put key </p>
  
  <p>Code for nav component:</p>
  
  <pre><code>var React = require('React');
  var $ = require('jquery');
  
  var Menubar = React.createClass({
      getInitialState: function() {
          return {
              items: []
          }
      },
      componentWillMount: function() {
          var _this = this;
          this.serverRequest =
          $.post("/nav", {}, function(result) {
             _this.setState({
                  items: result.data
              });
          })
     },
      render: function() {
          var item = this.state.items.map(function(data) {
              var ico = "fa fa-" + data.ico;
              return (
                 &lt;div id={data.sname} className="nav_item"&gt;
                      &lt;div className="nav_icon"&gt;
                            &lt;a href={data.url}&gt;
                                 &lt;i className = {ico}&gt;
                                 &lt;/i&gt;
                            &lt;/a&gt;
                      &lt;/div&gt;
                 &lt;/div&gt;   
          );
      });
      return (
          &lt;div&gt;{item}&lt;/div&gt;
      )
    }
  })
  module.exports = Menubar;
  </code></pre>