Primefaces valueChangeListener或< p:ajax侦听器未针对p:selectOneMenu触发

本文介绍了Primefaces valueChangeListener或< p:ajax侦听器未针对p:selectOneMenu触发的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我正在使用Primefaces 3.4.2.

I am using Primefaces 3.4.2.

我的JSF页面中有以下内容

I have the following in my JSF page

<p:selectOneMenu id="emp" value="#{mymb.emp.employeeName}" valueChangeListener="#{mymb.handleChange}" required="true" style="width: 150px;"> <f:selectItem noSelectionOption="true" itemLabel="Please Select"/> <f:selectItems value="#{mymb.employeeList}" var="emp" itemLabel="#{emp.employeeName}" itemValue="#{emp.employeeNumber}"/> <p:ajax update="sublist"/> </p:selectOneMenu>

和ManagedBean

and in ManagedBean

public void handleChange(ValueChangeEvent event){ System.out.println("here "+event.getNewValue()); }

问题是valueChangeListener没有触发，即handleChange方法没有被调用.我尝试了以下方法，但也无法正常工作.

The problem is valueChangeListener is not firing, i.e. handleChange method is not getting invoked. I tried with the following, but it is not working either.

<p:ajax update="sublist" listener="#{mymb.handleChange}" />

单独的JSF页面:

<ui:composition template="/templates/layout.xhtml" xmlns="www.w3/1999/xhtml" xmlns:f="java.sun/jsf/core" xmlns:h="java.sun/jsf/html" xmlns:ui="java.sun/jsf/facelets" xmlns:p="primefaces/ui"> <ui:define name="content"> <h:head> </h:head> <h:body> <h:form id="form"> <p:panelGrid columns="6"> <h:outputLabel value="Employees" for="employees" /> <p:selectOneMenu id="employees" value="#{mymb.employeesList}" required="true"> <f:selectItems value="#{mymb.employeesList}" var="emp" itemLabel="#{emp.employeeName}" /> <p:ajax listener="#{mymb.handleChange}" /> </p:selectOneMenu> </p:panelGrid> </h:form> </h:body> </ui:define> </ui:composition>

推荐答案

如果要使用valueChangeListener，则每次选择新选项时都需要提交表单.像这样:

If you want to use valueChangeListener, you need to submit the form every time a new option is chosen. Something like this:

<p:selectOneMenu value="#{mymb.employee}" onchange="submit()" valueChangeListener="#{mymb.handleChange}" > <f:selectItems value="#{mymb.employeesList}" var="emp" itemLabel="#{emp.employeeName}" itemValue="#{emp.employeeID}" /> </p:selectOneMenu> public void handleChange(ValueChangeEvent event){ System.out.println("New value: " + event.getNewValue()); }

否则，如果您想使用<p:ajax>，它应该看起来像这样:

Or else, if you want to use <p:ajax>, it should look like this:

<p:selectOneMenu value="#{mymb.employee}" > <p:ajax listener="#{mymb.handleChange}" /> <f:selectItems value="#{mymb.employeesList}" var="emp" itemLabel="#{emp.employeeName}" itemValue="#{emp.employeeID}" /> </p:selectOneMenu> private String employeeID; public void handleChange(){ System.out.println("New value: " + employee); }

要注意的一件事是，在您的示例代码中，我看到了<p:selectOneMenu>的value属性是#{mymb.employeesList}，它与<f:selectItems>的value相同. <p:selectOneMenu>的value应该类似于我上面的示例，该示例指向单个雇员，而不是雇员列表.

One thing to note is that in your example code, I saw that the value attribute of your <p:selectOneMenu> is #{mymb.employeesList} which is the same as the value of <f:selectItems>. The value of your <p:selectOneMenu> should be similar to my examples above which point to a single employee, not a list of employees.