public function columns()
    {
        if ($this->columns->isEmpty()) {
            $this->columns->push($this->current);
        }

        return $this->columns;
    }
public function columns()
    {
        if ($this->columns->isEmpty()) {
            $this->columns->push($this->current);
        }

        return $this->columns;
    }
public function columns ( ) { if ( $ this -> columns -> isEmpty ( ) ) { $ this -> columns -> push ( $ this -> current ) ; } return $ this -> columns ; }
Get all columns in filter layout.

@return Collection
Get all columns in filter layout .