我正在使用FormBuilder：Orbeon Forms 2016.2.1.201609272302 PE。
我一直在尝试从复选框控制字段中的已检查（选定）值创建一个动态填充的下拉列表（即，下拉列表中的每个选中的值都是选项）
这是我一直在使用的例子，
<xh:html xmlns:xh="http://www.w3.org/1999/xhtml" xmlns:xf="http://www.w3.org/2002/xforms" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ev="http://www.w3.org/2001/xml-events" xmlns:xi="http://www.w3.org/2001/XInclude" xmlns:xxi="http://orbeon.org/oxf/xml/xinclude" xmlns:xxf="http://orbeon.org/oxf/xml/xforms" xmlns:exf="http://www.exforms.org/exf/1-0" xmlns:fr="http://orbeon.org/oxf/xml/form-runner" xmlns:saxon="http://saxon.sf.net/" xmlns:sql="http://orbeon.org/oxf/xml/sql" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:fb="http://orbeon.org/oxf/xml/form-builder">
<xh:head>
<xh:title>gtest</xh:title>
<xf:model id="fr-form-model" xxf:expose-xpath-types="true">
<!-- Main instance -->
<xf:instance id="fr-form-instance" xxf:exclude-result-prefixes="#all" xxf:index="id">
<form>
<section-1>
<control-2>t5 t4</control-2>
<control-4/>
<control-3/>
</section-1>
</form>
</xf:instance>
<!-- Bindings -->
<xf:bind id="fr-form-binds" ref="instance('fr-form-instance')">
<xf:bind id="section-1-bind" name="section-1" ref="section-1">
<xf:bind id="control-2-bind" ref="control-2" name="control-2" />
<xf:bind id="control-3-bind" ref="control-3" name="control-3" />
<xf:bind id="control-4-bind" ref="control-4" name="control-4" calculate="$control-2" />
</xf:bind>
</xf:bind>
<!-- Metadata -->
<xf:instance xxf:readonly="true" id="fr-form-metadata" xxf:exclude-result-prefixes="#all">
<metadata>
<application-name>test</application-name>
<form-name>test</form-name>
<title xml:lang="en">gtest</title>
<description xml:lang="en">testing dynamic dropdown based on checklist values.</description>
</metadata>
</xf:instance>
<!-- Attachments -->
<xf:instance id="fr-form-attachments" xxf:exclude-result-prefixes="#all">
<attachments>
<css mediatype="text/css" filename="" size="" />
<pdf mediatype="application/pdf" filename="" size="" />
</attachments>
</xf:instance>
<!-- All form resources -->
<xf:instance xxf:readonly="true" id="fr-form-resources" xxf:exclude-result-prefixes="#all">
<resources>
<resource xml:lang="en">
<control-2>
<label>checklist</label>
<hint/><item><label>t1</label><hint/><value>t1</value>
</item><item><label>t2</label><hint/><value>t2</value>
</item><item><label>t3</label><hint/><value>t3</value>
</item><item><label>t4</label><hint/><value>t4</value>
</item><item><label>t5</label><hint/><value>t5</value>
</item><item><label>t6</label><hint/><value>t6</value>
</item><item><label>t7</label><hint/><value>t7</value>
</item>
</control-2>
<control-4>
<label>selected values</label>
<hint/>
</control-4>
<control-3>
<label>dynamic dropdown list</label>
<hint/>
<xf:itemset ref="$control-2">
<xf:label ref="." />
<xf:value ref="." />
</xf:itemset>
</control-3>
<section-1>
<label>Dropdown from checklist</label>
</section-1>
</resource>
</resources>
</xf:instance>
<!-- Utility instances for services -->
<xf:instance id="fr-service-request-instance" xxf:exclude-result-prefixes="#all">
<request/>
</xf:instance>
<xf:instance id="fr-service-response-instance" xxf:exclude-result-prefixes="#all">
<response/>
</xf:instance>
</xf:model>
</xh:head>
<xh:body>
<fr:view>
<fr:body xmlns:xbl="http://www.w3.org/ns/xbl" xmlns:p="http://www.orbeon.com/oxf/pipeline" xmlns:oxf="http://www.orbeon.com/oxf/processors">
<fr:section id="section-1-control" bind="section-1-bind">
<xf:label ref="$form-resources/section-1/label" />
<fr:grid>
<xh:tr>
<xh:td>
<xf:select id="control-2-control" appearance="full" bind="control-2-bind">
<xf:label ref="$form-resources/control-2/label" />
<xf:hint ref="$form-resources/control-2/hint" />
<xf:alert ref="$fr-resources/detail/labels/alert" />
<xf:itemset ref="$form-resources/control-2/item">
<xf:label ref="label" />
<xf:value ref="value" />
<xf:hint ref="hint" />
</xf:itemset>
</xf:select>
</xh:td>
</xh:tr>
<xh:tr>
<xh:td>
<xf:output id="control-4-control" bind="control-4-bind">
<xf:label ref="$form-resources/control-4/label" />
<xf:hint ref="$form-resources/control-4/hint" />
<xf:alert ref="$fr-resources/detail/labels/alert" />
</xf:output>
</xh:td>
</xh:tr>
<xh:tr>
<xh:td>
<fr:dropdown-select1 xmlns:xxbl="http://orbeon.org/oxf/xml/xbl" id="control-3-control" bind="control-3-bind">
<xf:label ref="$form-resources/control-3/label" />
<xf:hint ref="$form-resources/control-3/hint" />
<xf:alert ref="$fr-resources/detail/labels/alert" />
<xf:itemset ref="$form-resources/control-2/item[label=('t1', 't2', 't4')]">
<xf:label ref="label" />
<xf:value ref="value" />
<xf:hint ref="hint" />
</xf:itemset>
</fr:dropdown-select1>
</xh:td>
</xh:tr>
</fr:grid>
</fr:section>
</fr:body>
</fr:view>
</xh:body>
</xh:html>
如果我能够使用XPath或某些Orbeon函数将核对表值转换为逗号分隔列表，我将有一个解决方案：
<xf:itemset ref="$form-resources/control-2/item[label=(<list of values>)]">
<xf:label ref="label" />
<xf:value ref="value" />
<xf:hint ref="hint" />
</xf:itemset>
其中<list of values>看起来像't1', 't2', 't3'。