title: jQuery not selecting right option at form with dropdown
body: <p>I have a form on a modal with the following HTML:</p>
  
  <pre><code>&lt;div class="input-field col m2 s12"&gt;
    &lt;select id="user_id" name="user_id"&gt;
      &lt;option value="1"&gt;John&lt;/option&gt;
      &lt;option value="2"&gt;Jane&lt;/option&gt;
      &lt;option value="3"&gt;Joe&lt;/option&gt;
    &lt;/select&gt;
    &lt;label for="user_id"&gt;User&lt;/label&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>I want the right item to be selected when I click on an event with the following jQuery script:</p>
  
  <pre><code>$(document).ready(function () {
  
  $('#calendar').fullCalendar({
    themeSystem: 'jquery-ui',
    slotLabelFormat: "HH:mm",
    timeFormat: 'h:mm',
    businessHours: {
      start: '08:00', // a start time (10am in this example)
      end: '19:00', // an end time (6pm in this example)
    },
    header: {
      left: 'prev,next today',
      center: 'title',
      right: 'month,agendaWeek,agendaDay,listMonth'
    },
    buttonText: {
      today: 'Vandaag',
      month: 'Maand',
      week: 'Week',
      day: 'Dag',
      list: 'Lijst'
    },
    defaultView: 'month',
    weekNumbers: false,
    weekends: false,
    eventLimit: true, // allow "more" link when too many events
    events: 'urltoEvents',
  
    eventClick: function (calEvent, jsEvent, view) {
      var eventId = calEvent.id;
      var userId = calEvent.user_id;
      var comment = calEvent.comment;
      var startTime = calEvent.start_time;
      var startDate = calEvent.start_date;
      var endTime = calEvent.end_time;
      var endDate = calEvent.end_date;
  
  
      $("#updateEvent #start_time").val(startTime);
      $("#updateEvent #start_date").val(startDate);
      $("#updateEvent #end_time").val(endTime);
      $("#updateEvent #end_date").val(endDate);
      $("#updateEvent #user_id").val(userId).attr("selected", "selected");
      $("#updateEvent #eventId").val(eventId);
      $("#updateEvent #comment").val(comment);
      $('#updateEvent').modal('open');
    }
  });
  </code></pre>
  
  <p>Unfortunately this is not working and it's showing the first option as the selected one. Can somebody help me with this please? Thanks.</p>