Optgroup In Chosen Extension

Yii 1.1 Extensions
1

Hi,

How we can be handle optgroup in chosen extension. I want dropdownlist in following format:




<optgroup label="BS">

<option>Javed Iqbal Hunzai</option>

<option>Aslam Karim</option>

</optgroup>

<optgroup label="MS">

<option>Junaid Iqbal</option>

<option>Ubaid Ali</option>

</optgroup>

I have used chosen using following line of code:




echo Chosen::activeDropDownList($model, 'student_id', CHtml::listData(Common::getListStudent(), 'id', 'name'));

where Common::getListStudent() returns following array:




Array

(

    [0] => Array

        (

            [name] => Javed Iqbal Hunzai

            [id] => 25

        )

 

    [1] => Array

        (

            [name] => Ubaid Ali

            [id] => 26

        )

)