在spring mvc app中，下面的下拉列表没有填充任何值，即使sel_word.concepts集合中有很多值：
<form:select path="conceptSelected" size="5" style="min-width:600px">
<form:options items="${sel_word.concepts}"/>
</form:select>
要确认已填充sel_word.concepts列表并将其发送到视图，我：
1.) printed out the size of sel_word.concepts in the controller and
2.) populated a data table in the jsp with the contents of sel_word.concepts.
为了明确地显示，视图中的下表使用sel_word.concepts的值正确填充：
<datatables:table id="drugconcepts" data="${sel_word.concepts}" cdn="true" row="concept" theme="bootstrap2"
CssClass="table table-striped" paginate="false" info="false" filter="false"
cssStyle="width: 650px;" align="left" >
<datatables:column title="cui" cssStyle="width: 100px;" display="html">
<c:out value="${concept.rxcui}"/>
</datatables:column>
<datatables:column title="Names" cssStyle="width: 500px;" display="html">
<c:out value="${concept.str}"/>
</datatables:column>
</datatables:table>
因此sel_word.concepts中有值，这些值实际上是发送到jsp的。那么为什么这些值不会填充form:select下拉列表？如何更改代码以使下拉列表正确填充？
供参考，我已在文件共享网站上发布了model，view和controller的完整代码，您可以点击以下链接访问该网站。
您可以查看model by clicking on this link的代码
您可以查看模型by clicking on this link的DrugWord实体部分的代码
您可以查看view by clicking on this link的完整代码
您可以查看controller by clicking on this link的完整代码。
根据CodeChimp的请求，我发布了实际发送到浏览器的html，如下所示。这是我在浏览器中点击view source时得到的结果：
<form:form modelAttribute="medication" method="post" class="form-horizontal" >
<div class="control-group">
Drug Concepts:
<form:select path="conceptSelected" size="5" style="min-width:600px">
<form:options items="[1163058, 1163059, 1163060, 1163061, 1163062, 1163063, 1163064, 190521, 213460, 213461, 221052, 242679, 242680, 284620, 285028, 307650, 329484, 329485, 364596, 368153, 368253, 370502, 370503, 374813, 476143, 539824, 573348, 573349, 575077, 602392, 602393, 602394, 602395, 614534] itemValue="rxcui"/>
</form:select>
</div>
<div class="control-group">
Dosage Text:
<form:input path="dosagetext" />
</div>
<div class="control-group">
Route:
<form:input path="route" />
</div>
<div class="control-group">
Frequency:
<form:select path="freqSelected" items="[twice daily, as directed, as required, once a day, in the morning, once a day, once a day, before bed, four times daily, every other day, once a day, in the evening, three times daily]" size="5" style="min-width:600px"/>
</div>
<div class="control-group">
Duration:
<form:input path="duration" />
</div>
<div class="control-group">
Start Date:
</div>
<div class="control-group">
Status:
<form:input path="status" />
</div>
<form:hidden path="id"/>
<div class="form-actions">
<button type="submit">Add this medication</button> <h3>Link to delete will go here.</h3>
</div>
</form:form>
相比之下，服务器上JSP表单的代码如下：
<c:set var="method" value="post"/>
<c:url value="/patientscodes.html" var="actUrl"/>
<form:form modelAttribute="medication" method="${method}" class="form-horizontal" >
<div class="control-group">
Drug Concepts:
<form:select path="conceptSelected" size="5" style="min-width:600px">
<form:options items="${sel_word.concepts} itemValue="rxcui"/>
</form:select>
</div>
<div class="control-group">
Dosage Text:
<form:input path="dosagetext" />
</div>
<div class="control-group">
Route:
<form:input path="route" />
</div>
<div class="control-group">
Frequency:
<form:select path="freqSelected" items="${freqs}" size="5" style="min-width:600px"/>
</div>
<div class="control-group">
Duration:
<form:input path="duration" />
</div>
<div class="control-group">
Start Date:
</div>
<div class="control-group">
Status:
<form:input path="status" />
</div>
<form:hidden path="id"/>
<div class="form-actions">
<button type="submit">Add this medication</button> <h3>Link to delete will go here.</h3>
</div>
</form:form>
根据CodeChimp的请求，mvc-view-resolver.xml的代码：
<?xml version="1.0" encoding="UTF-8"?>
<!--
- DispatcherServlet application context for knowledgemanager's web tier.
-->
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:oxm="http://www.springframework.org/schema/oxm"
xsi:schemaLocation="http://www.springframework.org/schema/oxm
http://www.springframework.org/schema/oxm/spring-oxm.xsd
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd">
<!--
- The ContentNegotiatingViewResolver delegates to the InternalResourceViewResolver and BeanNameViewResolver,
- and uses the requested media type (determined by the path extension) to pick a matching view.
- When the media type is 'text/html', it will delegate to the InternalResourceViewResolver's JstlView,
- otherwise to the BeanNameViewResolver.
-->
<bean class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver">
<property name="contentNegotiationManager" ref="cnManager"/>
<property name="viewResolvers">
<list>
<!-- Default viewClass: JSTL view (JSP with html output) -->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<!-- Example: a logical view name of 'vets' is mapped to '/WEB-INF/jsp/vets.jsp' -->
<property name="prefix" value="/WEB-INF/jsp/"/>
<property name="suffix" value=".jsp"/>
</bean>
<!-- Used here for 'xml' and 'atom' views -->
<bean class="org.springframework.web.servlet.view.BeanNameViewResolver"/>
</list>
</property>
</bean>
<!-- Simple strategy: only path extension is taken into account -->
<bean id="cnManager" class="org.springframework.web.accept.ContentNegotiationManagerFactoryBean">
<property name="favorPathExtension" value="true"/>
<property name="ignoreAcceptHeader" value="true"/>
<property name="defaultContentType" value="text/html"/>
<property name="mediaTypes">
<map>
<entry key="html" value="text/html" />
<entry key="xml" value="application/xml" />
<entry key="atom" value="application/atom+xml" />
</map>
</property>
</bean>
</beans>
答案 0 :(得分：0)
按如下所示更改jsp，以包含itemValue和itemLabel：
<form:select path="conceptSelected" size="5" style="min-width:600px">
<form:options items="${sel_word.concepts}" itemValue="rxcui" itemLabel="str"/>
</form:select>