页面使用托管bean生成正确的值,但这两个h:selectOneMenu中的ajax事件不起作用。监听器未被调用。错误可能在标签内部,但我没有看到它。
<f:view>
<h:form>
<h:messages />
<h:panelGrid columns="3">
<h:outputLabel value="Choose your faculty: *" for="faculties" />
<h:selectOneMenu id="faculties" value="#{registrateStudent.selectedFaculty}" >
<f:ajax event="change" listener="#{registrateStudent.genSpecializations}" execute="faculties" render="specializations" />
<f:selectItems value="#{registrateStudent.listFaculty}" var="curFac" itemLabel="#{curFac.name}" itemValue="#{curFac}" />
</h:selectOneMenu>
<h:message id="message_faculties" for="faculties" />
<h:outputLabel value="Choose your specialization: *" for="specializations" />
<h:selectOneMenu id="specializations" value="#{registrateStudent.selectedSpecialization}" >
<f:selectItems value="#{registrateStudent.listSpecialization}" var="curSpec" itemLabel="#{curSpec.name}" itemValue="#{curSpec}"/>
</h:selectOneMenu>
<h:message id="message_specializations" for="specializations" />
托管 Bean:
@ManagedBean(name = "registrateStudent")
@ViewScoped
public class RegistrateStudent {
private Faculty selectedFaculty;
private List<Faculty> listFaculty;
private Specialization selectedSpecialization;
private List<Specialization> listSpecialization;
private boolean showSpecialization = false;
/** Creates a new instance of RegistrateStudent */
public RegistrateStudent() {
users = new Users();
System.out.println("poaposd1");
student = new Student();
}
@PostConstruct
public void init() {
listFaculty = ff.findAll();
if (listFaculty != null) {
selectedFaculty = listFaculty.get(0);
listSpecialization = sf.findByFaculty(selectedFaculty.getIdFaculty());
if (listSpecialization != null) {
selectedSpecialization = listSpecialization.get(0);
}
else {}
} else {}
}
public void genSpecializations(AjaxBehaviorEvent event) {
if (sf.findByFaculty(selectedFaculty.getIdFaculty()) != null) {
this.showSpecialization = true;
} else {
JsfUtil.addSuccessMessage("faculties", "We don't have specializations for such faculty");
}
}
}
更新:
我发现了一些有趣的事情:
<f:ajax>
标签在 <h:link>
、<h:selectOneMenu>
、<h:button>
、<h:commandButton>
中不起作用。在这种情况下,render
属性中的错误值不会被注意到,但是 event
属性中的错误值会生成错误。
<h:outputLabel>
、<h:inputText>
与 <f:ajax>
正常工作。