Yii2 - Render view located in subfolder - php

Question

I'm working with Yii2 and I wonder which is the right way to render from a controller a file located within a subfolder in views directory. For example, I have the following situation:
views
-campus (carpeta)
--actividad (subcarpeta)
---2020.php (vista)
So far, I've tried this options but without success:
return $this->render('/actividad/2020',[]);
return $this->render('/actividad/2020',[],$this->context);
return $this->render('2020',[],$this->context);
return $this->render('#app/views/campus/actividad/2020',[]);
return $this->render('//actividad/2020',[]);
My controller CampusController:
<?php
namespace frontend\controllers;
class CampusController extends \yii\web\Controller
{
public function action2020()
{
return $this->render('actividad/2020');
//return $this->render('/campus/actividad/2020');
//return $this->render('//campus/actividad/2020');
//return $this->render('#app/views/campus/actividad/2020');
}
}

Answer 1

If you are on CampusController, want to render 2020.php, and have the folder structure that you show in your question:
views
-campus (carpeta)
--actividad (subcarpeta)
---2020.php (vista)
All the following ways would work:
return $this->render('actividad/2020');
return $this->render('/campus/actividad/2020');
return $this->render('//campus/actividad/2020');
return $this->render('#app/views/campus/actividad/2020');
If you are not passing any parameters to the view, you can pass an empty array, but you can also remove the second parameter.
You do need to return the result of $this->render(...), in your question it looks like you are calling return after, that would return an empty response instead of the result of rendering the view file.