src/ItePHP/Component/Grid/Column.php
public function setSortBy($sortKeys){

		if($sortKeys==null){
			$sortKeys=[];
		}

		if(!is_array($sortKeys)){
			$sortKeys=[$sortKeys];
		}
		$this->sortKeys=$sortKeys;
	}
public function setSortBy($sortKeys){

		if($sortKeys==null){
			$sortKeys=[];
		}

		if(!is_array($sortKeys)){
			$sortKeys=[$sortKeys];
		}
		$this->sortKeys=$sortKeys;
	}
Set sortable column by Keys

@param mixed $sortKeys sort by list of id