public function order($columns)
    {
        foreach ($columns as $column => $position) {
            $this->positions[$column] = $position;
        }

        return $this;
    }
public function order($columns)
    {
        foreach ($columns as $column => $position) {
            $this->positions[$column] = $position;
        }

        return $this;
    }
public function order ( $ columns ) { foreach ( $ columns as $ column => $ position ) { $ this -> positions [ $ column ] = $ position ; } return $ this ; }
Define the postion for a columns
@param  string  $columns  an array of columns
Define the postion for a columns