javascript - Firebase-query with a progress bar (paper-progress) in Polymer

Question

I am trying to combine the firebase-query element with a paper-progress bar from Polymer. Unfortunately the firebase-query has no loading property such as the iron-ajax. So I tried to change the value of indeterminate in my paperprogress when the transections-complete fires inside my firebase-query. But I am unable to receive anything in my queryComplete function like it never get's called.

 <firebase-query
  id="query"
  path="/data/notes"
  data="{{notes}}"
  transactions-complete="{{queryComplete}}"></firebase-query>

 <paper-progress id="progressBar" step="2" indeterminate="true"></paper-progress>


 <script>
   Polymer({
     is: 'my-dashboard',

       properties: {
         notes: {
           type: Object,
         },
       },
       queryComplete: function(e) {
         var progressBar = this.$$("#progressBar");
         progressBar.setAttribute("indeterminate", "false");
       },

   });
 </script>