如何设置Orbeon元素的相关属性取决于是否访问过前一个元素？

Question

我试图在表单中创建一些元素，如果访问过某个特定元素，则这些元素是可见的。有可能吗？

此时，我只能实现将第一个元素的相关部分复制到其他元素中，但是，在一个元素的情况下依赖于许多其他元素，相关规则太大。然后我正在寻找一些简单的方法：是否有像“isVisible（）”这样的函数？

类似的东西（即只有当control-1可见时，control-2必须是可见的）：

<xf:bind id="control-2-bind" ref="control-2" name="control-2" relevant="isVisible($control-1)"/>

编辑： 表单的一个示例，其中只有在显示control-4时才必须显示control-5。

<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:xxforms="http://orbeon.org/oxf/xml/xforms"
     xmlns:fb="http://orbeon.org/oxf/xml/form-builder">
<xh:head>
    <xh:title>Untitled Form</xh:title>
    <xf:model id="fr-form-model" xxf:expose-xpath-types="true">

        <!-- Main instance -->
        <xf:instance id="fr-form-instance">
            <form>
                <section-1>
                    <control-3/>
                    <control-4/>
                    <control-5/>

                </section-1>
            </form>
        </xf:instance>

        <!-- Bindings -->
        <xf:bind xmlns:dataModel="java:org.orbeon.oxf.fb.DataModel" 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-3-bind" ref="control-3" name="control-3"/>
                <xf:bind id="control-4-bind" ref="control-4" name="control-4"
                         relevant="$control-3='one'"/>
                <xf:bind id="control-5-bind" ref="control-5" name="control-5"
                         relevant="xxforms:visited($control-4)"/>

            </xf:bind>
        </xf:bind>

        <!-- Metadata -->
        <xf:instance xxf:readonly="true" id="fr-form-metadata">
            <metadata>
                <application-name>asd</application-name>
                <form-name>asd</form-name>
                <title xml:lang="en">Untitled Form</title>
                <description xml:lang="en"/>
            </metadata>
        </xf:instance>

        <!-- Attachments -->
        <xf:instance id="fr-form-attachments">
            <attachments>
                <css mediatype="text/css" filename="" size=""/>
                <pdf mediatype="application/pdf" filename="" size=""/>
            </attachments>
        </xf:instance>

        <!-- All form resources -->
        <!-- Don't make readonly by default in case a service modifies the resources -->
        <xf:instance id="fr-form-resources" xxf:readonly="false">
            <resources>
                <resource xml:lang="en">
                    <control-3>
                        <item>
                            <label>First choice</label>
                            <value>one</value>
                        </item>
                        <item>
                            <label>Second choice</label>
                            <value>two</value>
                        </item>
                        <item>
                            <label>Third choice</label>
                            <value>three</value>
                        </item>
                        <label/>
                        <hint/>
                    </control-3>
                    <control-4>
                        <label>Input</label>
                        <hint/>
                    </control-4>
                    <control-5>
                        <label>Visited</label>
                        <hint/>
                    </control-5>
                    <section-1>
                        <label>Untitled Section</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:dataModel="java:org.orbeon.oxf.fb.DataModel"
                 xmlns:oxf="http://www.orbeon.com/oxf/processors"
                 xmlns:p="http://www.orbeon.com/oxf/pipeline">
            <fr:section id="section-1-control" bind="section-1-bind">
                <xf:label ref="$form-resources/section-1/label"/>
                <fr:grid>
                    <xh:tr>
                        <xh:td>
                            <xf:select1 id="control-3-control" appearance="full" bind="control-3-bind">
                                <xf:label ref="$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-3/item">
                                    <xf:label ref="label"/>
                                    <xf:value ref="value"/>
                                </xf:itemset>
                            </xf:select1>

                        </xh:td>

                    </xh:tr>
                    <xh:tr>
                        <xh:td>
                            <xf:input 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:input>
                        </xh:td>
                    </xh:tr>
                    <xh:tr>
                        <xh:td>
                            <xf:output id="control-5-control" bind="control-5-bind">
                                <xf:label ref="$form-resources/control-5/label"/>
                                <xf:hint ref="$form-resources/control-5/hint"/>

                                <xf:alert ref="$fr-resources/detail/labels/alert"/>
                            </xf:output>
                        </xh:td>
                    </xh:tr>
                </fr:grid>
            </fr:section>
        </fr:body>
    </fr:view>
</xh:body>

代码无效。控件-5从未显示过。有什么问题？

已编辑：使用建议的解决方案“instance（'visited'）”

的示例

<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:xxforms="http://orbeon.org/oxf/xml/xforms"
     xmlns:fb="http://orbeon.org/oxf/xml/form-builder">
<xh:head>
    <xh:title>Untitled Form</xh:title>
    <xf:model id="fr-form-model" xxf:expose-xpath-types="true">

    <!-- Main instance -->
    <xf:instance id="fr-form-instance">
            <form>
                <section-1>
                    <control-3/>
                    <control-4/>
                    <control-5/>
                </section-1>
            </form>
        </xf:instance>

        <!-- Bindings -->
    <xf:bind xmlns:dataModel="java:org.orbeon.oxf.fb.DataModel" 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-3-bind" ref="control-3" name="control-3"/>
                <xf:bind id="control-4-bind" ref="control-4" name="control-4"
                         relevant="$control-3='one'"/>
                <xf:bind id="control-5-bind" ref="control-5" name="control-5"
                         relevant="instance('visited') = 'true' and string-length($control-4)&gt;0"/>
            </xf:bind>
        </xf:bind>

        <!-- Keep track of visited status -->
    <xf:instance id="visited">
            <visited/>
        </xf:instance>
        <xf:setvalue ev:event="xxforms-visited" observer="control-4-control"
                     ref="instance('visited')"
                     value="'true'"/>
        <xf:setvalue ev:event="xxforms-unvisited" observer="control-4-control"
                     ref="instance('visited')"
                     value="'false'"/>

        <!-- Metadata -->
    <xf:instance xxf:readonly="true" id="fr-form-metadata">
            <metadata>
                <application-name>asd</application-name>
                <form-name>asd</form-name>
                <title xml:lang="en">Untitled Form</title>
                <description xml:lang="en"/>
            </metadata>
        </xf:instance>

        <!-- Attachments -->
    <xf:instance id="fr-form-attachments">
            <attachments>
                <css mediatype="text/css" filename="" size=""/>
                <pdf mediatype="application/pdf" filename="" size=""/>
            </attachments>
        </xf:instance>

        <!-- All form resources -->
    <!-- Don't make readonly by default in case a service modifies the resources -->
    <xf:instance id="fr-form-resources" xxf:readonly="false">
            <resources>
                <resource xml:lang="en">
                    <control-3>
                        <item>
                            <label>First choice</label>
                            <value>one</value>
                        </item>
                        <item>
                            <label>Second choice</label>
                            <value>two</value>
                        </item>
                        <item>
                            <label>Third choice</label>
                            <value>three</value>
                        </item>
                        <label/>
                        <hint/>
                    </control-3>
                    <control-4>
                        <label>Input</label>
                        <hint/>
                    </control-4>
                    <control-5>
                        <label>Visited</label>
                        <hint/>
                    </control-5>
                    <section-1>
                        <label>Untitled Section</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:oxf="http://www.orbeon.com/oxf/processors"
                 xmlns:p="http://www.orbeon.com/oxf/pipeline"
                 xmlns:dataModel="java:org.orbeon.oxf.fb.DataModel">
            <fr:section id="section-1-control" bind="section-1-bind">
                <xf:label ref="$form-resources/section-1/label"/>
                <fr:grid>
                    <xh:tr>
                        <xh:td>
                            <xf:select1 id="control-3-control" appearance="full" bind="control-3-bind">
                                <xf:label ref="$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-3/item">
                                    <xf:label ref="label"/>
                                    <xf:value ref="value"/>
                                </xf:itemset>
                            </xf:select1>

                        </xh:td>

                    </xh:tr>
                    <xh:tr>
                        <xh:td>
                            <xf:input 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="$fr-resources/detail/labels/alert"/>
                            </xf:input>
                        </xh:td>
                    </xh:tr>
                    <xh:tr>
                        <xh:td>
                            <xf:output id="control-5-control" bind="control-5-bind">
                                <xf:label ref="$form-resources/control-5/label"/>
                                <xf:hint ref="$form-resources/control-5/hint"/>
                                <xf:alert ref="$fr-resources/detail/labels/alert"/>                                
                            </xf:output>
                        </xh:td>
                    </xh:tr>
                </fr:grid>
            </fr:section>
        </fr:body>
    </fr:view>
</xh:body>

在此示例中，如果选择“First Choice”，则会显示“输入字段”。如果您填写任何值，则会显示“已访问”标签。这是预期的行为。但是，如果您稍后将单选按钮更改为“第二选择”，则输入字段将被隐藏，但“已访问”标签仍然可见（仅当用户删除输入字段的值时才会隐藏，但现在已隐藏） 。这是不希望的。有什么方法可以避免这种情况吗？

注意：我添加了string-length（）以确保在删除值时隐藏它。没有它，总是可见的。

Answer 1

自Orbeon Forms 4以来，有：

• xxf:visited() function
• xxforms-visited和xxforms-unvisited事件

使用该函数时必须小心依赖关系，尤其是xf:bind。

我试图建立一个天真的例子，但事实证明它不起作用，我输入了an issue。

这是一种解决方法，需要添加自定义XForms实例：

<xf:bind id="control-5-bind" ref="control-5" name="control-5"
    relevant="instance('visited') = 'true'"/>

<xf:instance id="visited"><visited/></xf:instance>
<xf:setvalue event="xxforms-visited"   observer="control-4-control" ref="instance('visited')" value="'true'"/>
<xf:setvalue event="xxforms-unvisited" observer="control-4-control" ref="instance('visited')" value="'false'"/>

这是complete example。