如何修改XSL-FO样式表在A4页高效放置多份发票（Apache FOP）

你当前的样式表中，每个<Invoice_Download>都会生成独立的<fo:page-sequence>，这是导致每份发票独占一页的核心原因——每个page-sequence对应PDF里的一页（即便发票内容仅占1/3页面）。

要实现多发票紧凑排版且不拆分，需把所有发票放在**同一个page-sequence**中，同时给每个发票的容器块添加不拆分规则。具体修改如下：

1. 调整根模板，统一生成单个page-sequence #

将原来分散生成多个page-sequence的逻辑，改为在一个page-sequence的flow里渲染所有发票，同时保留第一页显示标题的页眉规则：

<xsl:template match="/">
  <fo:root>
    <fo:layout-master-set>
      <fo:simple-page-master master-name="invoice-page" page-width="21cm" margin="0.5cm">
        <fo:region-body margin="1cm" />
        <fo:region-before extent="3cm" />
        <fo:region-after extent="0.5cm" />
      </fo:simple-page-master>
      <!-- 区分第一页与后续页的模板引用，实现仅第一页显示标题 -->
      <fo:page-sequence-master master-name="invoice-sequence">
        <fo:repeatable-page-master-alternatives>
          <fo:conditional-page-master-reference master-reference="invoice-page" page-position="first" />
          <fo:conditional-page-master-reference master-reference="invoice-page" />
        </fo:repeatable-page-master-alternatives>
      </fo:page-sequence-master>
    </fo:layout-master-set>

    <!-- 仅创建一个page-sequence，承载所有发票内容 -->
    <fo:page-sequence master-reference="invoice-sequence">
      <fo:static-content flow-name="xsl-region-before">
        <fo:block text-align="center" font-size="18pt">
          <xsl:if test="page-position()='first'">INVOICES</xsl:if>
        </fo:block>
      </fo:static-content>
      <fo:flow flow-name="xsl-region-body">
        <xsl:apply-templates select="Download/Invoice_Download"/>
      </fo:flow>
    </fo:page-sequence>
  </fo:root>
</xsl:template>

2. 修改Invoice_Download模板，生成可堆叠的发票块 #

去掉原模板中的<fo:page-sequence>，改为生成包裹发票内容的块，并添加keep-together.within-page="always"确保整个发票不被拆分到两页：

<xsl:template match="Invoice_Download">
  <!-- 用block包裹发票内容，添加不拆分规则与间距区分不同发票 -->
  <fo:block keep-together.within-page="always" margin-bottom="1cm">
    <!-- 替换为你原来的发票具体内容 -->
    ...........
  </fo:block>
</xsl:template>

关键说明 #

• 单个page-sequence：所有发票都在同一个page-sequence的flow中，Apache FOP会自动将能放下的发票排在同一页，空间不足时自动分页。
• keep-together.within-page="always"：强制每个发票作为完整整体，不会被拆分到两页。
• 页眉控制：通过page-position()='first'实现仅第一页显示"INVOICES"标题，后续页页眉为空，匹配原需求。

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:fo="http://www.w3.org/1999/XSL/Format">
  <xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>

  <xsl:template match="/">
    <fo:root>
      <fo:layout-master-set>
        <fo:simple-page-master master-name="invoice-page" page-width="21cm" margin="0.5cm">
          <fo:region-body margin="1cm" />
          <fo:region-before extent="3cm" />
          <fo:region-after extent="0.5cm" />
        </fo:simple-page-master>
        <fo:page-sequence-master master-name="invoice-sequence">
          <fo:repeatable-page-master-alternatives>
            <fo:conditional-page-master-reference master-reference="invoice-page" page-position="first" />
            <fo:conditional-page-master-reference master-reference="invoice-page" />
          </fo:repeatable-page-master-alternatives>
        </fo:page-sequence-master>
      </fo:layout-master-set>

      <fo:page-sequence master-reference="invoice-sequence">
        <fo:static-content flow-name="xsl-region-before">
          <fo:block text-align="center" font-size="18pt">
            <xsl:if test="page-position()='first'">INVOICES</xsl:if>
          </fo:block>
        </fo:static-content>
        <fo:flow flow-name="xsl-region-body">
          <xsl:apply-templates select="Download/Invoice_Download"/>
        </fo:flow>
      </fo:page-sequence>
    </fo:root>
  </xsl:template>

  <xsl:template match="Invoice_Download">
    <fo:block keep-together.within-page="always" margin-bottom="1cm">
      <!-- 替换为你的发票具体内容 -->
      ...........
    </fo:block>
  </xsl:template>
</xsl:stylesheet>

内容的提问来源于stack exchange，提问作者ashish