joomla3.0 - How to change select list from another using AJAX in Joomla -

i have list of countries , list of cities each country. set both drop-down list.

my problem how can change cities listed when selected country changes?

this xml code:

<field name="country_id" type="sql" class="country" label="country"        description="country" required="true"        query="select id, title #__destination_countries state = 1"        key_field="id" value_field="title" filter="raw"> </field>   <field name="city_id" type="sql"        query="select id, title #__destination_cities state = 1"        key_field="id" value_field="title" class="city" label="city"        description="city" required="true" filter="raw"> </field>  

ajax code:

jquery(document).ready(function($) {     $(".country").change(function(){         country_id = $("#" + this.id).val();         $.ajax({             url:'index.php?option=com_destination&task=cities.getlistcities',             type: "post",             data: {                 'country_id': country_id             }         }).done(function(msg) {             console.log(msg);             $(".city").html(msg);          })     }) }); 

this server-side code

public function getlistcities() {     $country_id = jrequest::getint('country_id', 0);     $model = $this->getmodel();     $model->setstate('filter.country_id', $country_id);     $items = $model->getitems();     $option = array();     foreach ($items $key => $item) {         $option[] = "<option value='{$item->id}'>{$item->title}</option>";     }     $return = implode("", $option);     echo $return;     exit; } 

but did not show want, show

<select style="display: none;" required="required" id="jform_city_id" name="jform[city_id]" class="city required chzn-done">     <option value="1">city 1 of coutry 1</option> </select> <div style="width: 220px;" class="chzn-container chzn-container-active" id="jform_city_id_chzn">     <a tabindex="-1" href="javascript:void(0)" class="chzn-single chzn-single-with-drop">         <span>city 1 of coutry 1</span>         <div><b></b></div>     </a>     <div class="chzn-drop" style="display: block; width: 218px; top: 24px;">         <div class="chzn-search"><input tabindex="-1" style="width: 183px;" autocomplete="off" type="text"></div>         <ul class="chzn-results">             <li id="jform_city_id_chzn_o_0" class="active-result" style="">city 1 of coutry 1</li>             <li id="jform_city_id_chzn_o_1" class="active-result result-selected" style="">city 2 of coutry 1</li>         </ul>     </div> </div> 

just change select option did not change below.

a note appart, you're using deprecated jrequest::getint(); should using

$input = jfactory::getapplication()->input; $country_id = $input->getint('country_id', 0); 

in order change second select, must trigger update of second select:

$(".country").change(function(){     // ajax call code      // on success, need trigger second select using     $( ".city_id" ).val(your_value_from_ajax_response).trigger( "liszt:updated" );  });