Search In Yii Cgridview

Hi..

I want to implement a search and i kinda did it statically. How can i make it dynamic ?

My Controller :

        $this -> layout = 'main';
        $model->notificationTitle = 'test'; //Static Value which i want to make it dynamic like $_GET['keywords']; or something       
        $this->render('notifications' ,array('model' => $model));	

Model :

        $criteria=new CDbCriteria;
        $criteria->compare('notificationTitle',$this->notificationTitle,true);

This works perfectly. How will i deploy a form in view and how can i get the values in controller?

Possible View ? :

<?php
 $form = $this->beginWidget('CActiveForm', array(
                'action' => Yii::app()->createUrl($this->route),
                'method' => 'post',
            ));
         echo $form->textField($model, 'notificationTitle', array('class' => 'field')); 
         $this->endWidget(); 
?>  

I know the view is wrong since its already filled up by last content. My view is a list view done using cgrid view. The search is outside the cgrid view and how can i pass the value in the search box to controller?