How to pass variable from AccessFilter to controller in Yii2

I have an AccessFilter class

class ProjectAccessControl extends \yii\base\ActionFilter
{
   public $a;
   /**
    * @inheritdoc
    */
   public function beforeAction($action)
   {
        switch ($action->id) {
          case 'view':
             // code here
             break;
        }
   }

      

        
        
        
      

    

In the controller, I override this AccessFilter method in behavior () like this:

public function behaviors()
{
    return [
        'access' => [
            'class' => ProjectAccessControl::className(),
        ]
    ];
}

      

        
        
        
      

    

Now I want to pass a variable $a

from AccessFilter to any action in the controller. How to do it?