[Problème] limiter l'affichage des select a 3

[lunadev]

Bonjour je travail avec virtuemart j'ai ajouter un module qui filter les catégories sauf que a chaque ajout d'une nouvelle catégories un select est ajouté , je veux limiter l'affichage des select a 3 seulement , voici le code :

public static function getCategoriesTree($params){

	$db = JFactory::getDBO();
		$query = $db->getQuery(true);

		$query->from('#__virtuemart_categories_'.VMLANG.' AS l');

		$query->join('INNER', '#__virtuemart_categories AS c using (virtuemart_category_id)');
		$query->join('LEFT', '#__virtuemart_category_categories AS cx ON l.virtuemart_category_id = cx.category_child_id ');

		$query->select('c.virtuemart_category_id as id,  l.category_name as title, cx.category_child_id as child_id, cx.category_parent_id as parent_id');

		$query->where('c.published = 1');

		if ($params->get('ordering', 'ordering') == 'title') {
			$query->order('l.category_name');
		} else {
			$query->order('cx.ordering');
		}
		//echo $query->dump();
		$db->setQuery($query);

		$results = $db->loadObjectList('id');
		if (empty($results)) {
			return array();
		}

		$categories = array();
		$categories[0] = (object) array(
			'id' => 0,
			'parent_id' => null,
			'title' => 'Top Level Category'
		);
		$categories += $results;
		$i = 1;
                
		foreach ($categories as $cat) {
                    
			//Ordre
			$categories[$cat->id]->ordering = $i;

			if (empty($categories[$cat->id]->children)) {
				$categories[$cat->id]->children = array();
			}
			//L'element fils
                        
			if (isset($categories[$cat->parent_id])) {
				if (empty($categories[$cat->parent_id]->children)) {
					$categories[$cat->parent_id]->children = array();
				}
                               $p= $categories[$cat->parent_id] ;
                             
				$categories[$cat->parent_id]->children[] = $cat;
                }
                     $i++; 
		}

		return $categories;

et la fonction du code js est :

updateTree: function (changed){
		//var id;//id of selected children

		//change event
		this.fireEvent('changed', [changed]);

		if(changed){

			//clear all after changed
			changed.getAllNext('label').destroy().empty();
			changed.getAllNext('select').destroy().empty();

			//add children select
			var id = changed.get('value');
			//get children JSON if link is given and tree empty
			if (this.options.request_url && id != this.options.empty_value && !this.tree[id]){
				this.requestChildren(changed);
			} else {//add select
                       }
                    this.addSelect(id)  
                       
                    ;
			
		} else {
			//cleare and build new
			this.element.getChildren('label').destroy().empty();
			this.element.getChildren('select').destroy().empty();
			//build new
			this.addSelect();
		}

	},

Quelqu'un pourrait m'aider s'il vous plait ? Merci beaucoup