DataGrid head 居中对齐

<s:GridColumn dataField="supplier_no" headerText="供应商编号">
                    <s:headerRenderer>
                        <fx:Component>
                            <s:DefaultGridHeaderRenderer>
                                <s:labelDisplay>
                                    <s:Label verticalCenter="1" left="0" right="0" top="0" bottom="0" textAlign="center" fontWeight="bold" verticalAlign="middle" maxDisplayedLines="1" showTruncationTip="true"/>
                                </s:labelDisplay>
                            </s:DefaultGridHeaderRenderer>
                        </fx:Component>
                    </s:headerRenderer>
                </s:GridColumn>