错误“Closure对象不能具有属性”

Question

This function is throwing me a "Closure object cannot have properties" error :

public function activitiesSummaryAction()
    {
        $classes = array();

        for($i = 1; $i <=10; $i++)
        {
            array_push($classes, new Classroom($i, function(){

                $activites = array();

                for ($i = 1; $i <=10; $i++)
                {
                    array_push($activites, new Activity(rand(1,7), rand(2016,2018)));
                }

                return $activites;
              }
           ));
        }


        return $this->render('teacher/activitiesSummary.html.twig', [
            'classes' => $classes,
        ]);
    }

Actually I'am not sure if PHP can support this kind of callback functions. Could anyone tell me how to correct this or make it work in another way?

EDITED: Here are the classes Classroom and Activity:

class Activity {

    public $_id;
    public $_annee;
    public $_inProgress;

    function __construct($id, $annee) {
        $this->_id = $id;
        $this->_annee = $annee;
        $this->_inProgress = rand(0,1);
    }
}


class Classroom {
    public $_id;
    public $_activities;

    function __construct($id, $activities) {
        $this->_id = $id;
        $this->_activities = array($activities);
    }
}

Answer 1

You need to use call_user_func(). Create a function you want to use as a callback:

function myCallback(){
    $activites = array();
    for ($i = 1; $i <=10; $i++)
    {
       array_push($activites, new Activity(rand(1,7), rand(2016,2018)));
    }
    return $activites;
}

then you need to use call_user_func() in the constructor:

class Classroom {
    public $_id;
    public $_activities;

    function __construct($id, $activities) {
      $this->_id = $id;
      $this->_activities = array(call_user_func($activities));
    }
}

in the end edit the code you posted here:

public function activitiesSummaryAction()
{
    $classes = array();

    for($i = 1; $i <=10; $i++)
    {
        array_push($classes, new Classroom($i, 'myCallback'));
    }


    return $this->render('teacher/activitiesSummary.html.twig', [
        'classes' => $classes,
    ]);
}