jQuery not selecting right option at form with dropdown

Question

I have a form on a modal with the following HTML:

<div class="input-field col m2 s12">
  <select id="user_id" name="user_id">
    <option value="1">John</option>
    <option value="2">Jane</option>
    <option value="3">Joe</option>
  </select>
  <label for="user_id">User</label>
</div>

I want the right item to be selected when I click on an event with the following jQuery script:

$(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');
  }
});

Unfortunately this is not working and it's showing the first option as the selected one. Can somebody help me with this please? Thanks.

Answer 1

Try next solution, since i don't know what is "#updateElement" i will ignore it.

var userId = calEvent.user_id;
$("#user_id").val(userId).change();

Also, the variable userId should hold values of type string, for example: "1", "2" or "3".

Answer 2

If you are just trying to set the user id for the selected box and assuming, for example, that the user id is #2 is in the value of the options list then all you need to do is this.

  $("#user_id").val("2");

However, your title suggests that you are not trying to set the value of the selected option but rather to read the selected value.

$("#user_id").on("change", function() {
   console.log("User ID: " +  $("#user_id option:selected").val());
   console.log("User Name: " +  $("#user_id option:selected").text());
});

Answer 3

After trying a lot the answer was quiet simple. I am not sure if it's because I am using 'Materialize', but I had to add 'formSelect()' to the code, so this was working for me:

$("#user_id").val(userId).change();
$("#user_id").formSelect();