How to add a placeholder to an exposed date filter form field? This is the structure of a date field in my exposed form:

&lt;input id="edit-date-filter-value-datepicker-popup-0" class="form-text hasDatepicker date-popup-init" type="text" maxlength="200" size="20" value="" name="date_filter[value][date]"&gt;


I added this code under

function bartik_form_views_exposed_form_alter(&amp;$form, &amp;$form_state) {}


to add place holder.

$form['date_filter']['#attributes']['placeholder'] = t('YYYY-MM-DD');


But place holder is not coming. Can anyone help?
jQuery may be a solution.

jQuery(document).ready(function(){ 
 jQuery('#edit-date-filter-value-datepicker-popup-0').attr("placeholder", "placeholder to show");
});