Can't get data from a codeigniter function with ajax - php

Question

This is what I've got so far:
This function that returns data from the model:
function get_user2()
{
$this->load->model('my_model');
$id=$this->input->post('users1');
$users2=$this->my_model->get_relations($id);
return $users2;
}
the model function:
function get_relations($usr)
{
$this->db->where('id',$usr);
$rel=$this->db->get('relacion');
if($rel->num_rows!=0)
{
$relacion=array();
foreach ($rel->result_array() as $row)
{
$relacion[]=array(
'id'=>$row['id'],
'username1'=>$row['username1'],
'username2'=>$row['username2'],
);
}
return $relacion;
}else{
return false;
}
}
and in my view:
<select name="users1" id="drop1">
<?php
if($opciones!=false){
foreach ($opciones as $row) {
echo '<option value="'.$row['user_id'].'">'.$row['username'].'</option>';
}
}
?>
</select>
<script src="jquery.js"></script>
<script type="text/javascript">
$("#drop1").change(function(){
$.ajax({
type: "POST",
url: "example.com/CI/index.php/evaluation/get_user2",
data: "users1="+$('#drop1').val(),
success: function(){
alert('it works!');
}
});
});
</script>
I want to fill a second dropdown with the options returned by the controller function, but the ajax request doesn't do anything so I haven't even got to that part. Can someone help me spot what's wrong? I already tested the controller and model's function and they work. And could you tell me how to fill the second dropdown's options?
Thank you very much!

Answer 1

Well I've a very similar code in one project to get some cities depending on the island the user choose. So wen the select changes, load the cities and enables the second select. The main difference is the way you pass the data.
<script type="text/javascript">
$("#idisla").change(function(){
if($("#idisla").val()!=""){
var dato=$("#idisla").val();
$.ajax({
type:"POST",
dataType:"html",
url:base_url+"admin/centros/municipios_select",
data:"idislajs="+dato,
success:function(msg){
$("#idmunicipio").empty().removeAttr("disabled").append(msg);
callback();
}
});
}else{
$("#idmunicipio").empty().attr("disabled","disabled");
}
});
</script>
The function only looks cities from the selected islad (id)
function municipios_select()
{
//el idIsla viene dado por el value del combo islas
$isla = $this->input->post('idislajs');
$data['municipios'] = $this->municipios_model->obtenMunicipios($isla);
echo $this->load->view("site/municipios_select",$data, TRUE);
}