public function addColumn(FieldConfig $column)
    {
        if ($this->columns === null) {
            $this->setColumns([]);
        }
        $this->columns->push($column);
        return $this;
    }
public function addColumn(FieldConfig $column)
    {
        if ($this->columns === null) {
            $this->setColumns([]);
        }
        $this->columns->push($column);
        return $this;
    }
public function addColumn ( FieldConfig $ column ) { if ( $ this -> columns === null ) { $ this -> setColumns ( [ ] ) ; } $ this -> columns -> push ( $ column ) ; return $ this ; }
Adds column to grid.

@param FieldConfig $column
@return $this
Adds column to grid .