add custom field in prestashop while creating new cart rule.

[newbie_prestashop]

Hi,

 

Problem while saving custom field which is add in cart rule condition .

Created one field 'usertype' in ps_cart_rule table..also define in cartrule.php like
public $usertype;

'usertype' => array('type' => self::TYPE_INT),

 

in condition.tpl i have write,

<select name="selecttype">

<option value="0"> Select Type </option>

{foreach from=$resultstype item=type}

<option value="{$type['id']}"> {$type['name']}</option>

{/foreach}

</select>

 

where can i write code for save selecttype?