fo：for-each不是fo：table-row的有效子项

Question

我正在使用Apache FOP 2.1在简单的Java应用程序中生成PDF文档。

当涉及生成具有动态行的表时，它总是以错误结束： (Position des Fehlers unbekannt)org.apache.fop.fo.ValidationException: "fo:for-each" is not a valid child of "fo:table-row"! (Keine Kontextinformationen verfügbar)

我的xml输入如下：

<?xml version="1.0"?>
<invoicedata>
  <invoice>
    <positions>
      <position>
        <posOrder>1</posOrder>
        <quantity>2</quantity>
      </position>
      <position>
        <posOrder>2</posOrder>
        <quantity>1</quantity>
      </position>
    </positions>
  </invoice>
</invoicedata>

我的xsl fo模板看起来像：

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.1" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:fo="http://www.w3.org/1999/XSL/Format"
  exclude-result-prefixes="fo">
  <xsl:template match="invoicedata">
    <fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format">
      <fo:layout-master-set>
        <fo:simple-page-master master-name="A4" page-height="297mm" page-width="210mm"
          margin-top="0.5cm" margin-bottom="0.5cm" margin-left="2cm" margin-right="2cm">
          <fo:region-body region-name="xsl-region-body" margin-bottom="3.5cm" margin-top="5cm" />
        </fo:simple-page-master>
      </fo:layout-master-set>

      <fo:page-sequence master-reference="A4">
        <fo:flow flow-name="xsl-region-body" font-size="10pt">
          <xsl:if test="invoice/positions">
            <fo:block>
              <fo:table table-layout="fixed" width="100%" border-style="solid" border-width="1pt"                >
                <fo:table-column column-width="7%" border-style="solid" border-width="1pt" />
                <fo:table-column column-width="8%" border-style="solid" border-width="1pt" />
                <fo:table-header background-color="gray">
                  <fo:table-row>
                    <fo:table-cell border-style="solid" border-width="1pt" >
                      <fo:block text-align="center">Pos.</fo:block>
                    </fo:table-cell>
                    <fo:table-cell border-style="solid" border-width="1pt" >
                      <fo:block text-align="center">Menge</fo:block>
                    </fo:table-cell>
                  </fo:table-row>
                </fo:table-header>
                <fo:table-body>
                  <fo:table-row>
                    <fo:for-each select="invoice/positions">
                    <fo:table-cell >
                      <fo:block text-align="right">
                        <xsl:value-of select="posOrder" />
                      </fo:block>
                    </fo:table-cell>
                    <fo:table-cell >
                      <fo:block text-align="right">
                        <xsl:value-of select="quantity" />
                      </fo:block>
                    </fo:table-cell>
                    </fo:for-each>
                  </fo:table-row>
                </fo:table-body>
              </fo:table>
            </fo:block>
          </xsl:if>
        </fo:flow>
      </fo:page-sequence>
    </fo:root>
  </xsl:template>

</xsl:stylesheet>

所以，atm我不知道如何配置for-each元素来生成一个包含动态行的表。