file-upload.html

<link rel="import" href="../bower_components/polymer/polymer.html">

<polymer-element name="polymer-file-upload"  attributes="">
  <template>
    <style>
      /* styles for the custom element itself - lowest specificity */
      :host { display: block; }
      /* 
      style if an ancestor has the different class
      :host(.different) { } 
      */
    </style>
    <input id="FileUpload" type="file">
  </template>
  <script>
    Polymer('polymer-file-upload', {
      //applyAuthorStyles: true,
      //resetStyleInheritance: true,

      // element is fully prepared
      ready: function(){ 
        var fileUpload = document.getElementById("FileUpload");
        console.log(fileUpload);
      },
      // instance of the element is created
      created: function() { 
        var fileUpload = document.getElementById("FileUpload");
        console.log(fileUpload);
      },
      // instance was inserted into the document
      enteredView: function() { 
        var fileUpload = document.getElementById("FileUpload");
        console.log(fileUpload);
      },
      // instance was removed from the document
      leftView: function() { },
      // attribute added, removed or updated
      attributeChanged: function(attrName, oldVal, newVal) {
        console.log(attrName);
      }
    });
    document.addEventListener('WebComponentsReady', function() {
        // Perform some behaviour
        var fileUpload = document.getElementById("FileUpload");
        // fileUpload.addEventListener("change", function(event){
        //  console.log(event);
        // });
    });
  </script>
</polymer-element>