Why doesn't jQuery UI Datepicker open the first time?

Question

JavaScript

in a RoR application (Rails 4.0.3), does the calendar only appear if the page is refreshed again? how to fix?
application.js //= require jquery.ui.datepicker
application.css.scss *= require jquery.ui.datepicker
posts.js

jQuery ->
$('#pticket_starts_at').datepicker
 dateFormat: 'yy-mm-dd'

Answer 1

As I read in one more or less authoritative book:

4 rails are wonderful. The first thing to do is remove the gem 'turbolinks' line