Resubmittion in Yii

I have made wizard kinda thing, where there will be a search option, search results will be shown in list. The list items have a radio button each. when i select a radio button and proceed further its good but if from this very next page I want to come back its asking me for resubmition the data. Although I have stored the searching values in session and in controller I wrote an another condition for this session. But alas!! its still want to resubmit the data. Where am I going wrong? Please give me some suggestion about this situation. Here is the controller action





public function actionContinue(){

   if ($_POST['radioButtonValue']){

       Yii::app()->session['_radio']=$_POST['radioButtonValue'];

       ....

       ....

       $this->render('view');

   }

   if (isset(Yii::app()->session['_radio'])){

       ....

       ....

       $this->render('view');

   }

}