Jsf 2 填充第二个素数面选择一个菜单

我有两个选择菜单。我从selectOneMenu1中选择项，并将项值添加到查询的where条件中。查询结果成功。但我没有将查询结果放入selectOneMenu2。selectOneMenu2每次都为空。我添加了关于这个问题的managedBean和xhtml页面代码

//Birimanagedbean关于上述问题

@Override
public void processAjaxBehavior(AjaxBehaviorEvent event) throws AbortProcessingException {
    String birimRequested = deger;
    byte birimId = Byte.parseByte(
    bolumManagedBean.bolumBilgileriniGetir(birimId);
}

public void bolumBilgileriniGetir(byte id) {
    bolumler = new ArrayList<Bolum>();
    Session session = HibernateUtil.getSessionFactory().openSession();

    Query query = session.createQuery("from Bolum b where b.birim.birim_id = :id");
    query.setParameter("id", id);
    bolumler = query.list();

<p:selectOneMenu id="birimi" value="#{birimMBean.deger}" style="float: left;" >
                <f:selectItems value="#{birimMBean.birimler}" var="birim" itemLabel="#{birim.birim_adi}" itemValue="#{birim.birim_id}" />
                <p:ajax event="change" listener="#{birimMBean.processAjaxBehavior}" />        
            </p:selectOneMenu>
            <br/><br/>
            <p:selectOneMenu id="bolumu" value="#{bolumMBean.secilenBolum}" style="float: left;">
                <f:selectItems value="#{bolumMBean.bolumler}" var="bolum" itemLabel="#{bolum.bolum_adi}" itemValue="#{bolum.bolum_id}" />
            </p:selectOneMenu>

//BolummangedBean关于上述问题

@Override
public void processAjaxBehavior(AjaxBehaviorEvent event) throws AbortProcessingException {
    String birimRequested = deger;
    byte birimId = Byte.parseByte(
    bolumManagedBean.bolumBilgileriniGetir(birimId);
}

public void bolumBilgileriniGetir(byte id) {
    bolumler = new ArrayList<Bolum>();
    Session session = HibernateUtil.getSessionFactory().openSession();

    Query query = session.createQuery("from Bolum b where b.birim.birim_id = :id");
    query.setParameter("id", id);
    bolumler = query.list();

<p:selectOneMenu id="birimi" value="#{birimMBean.deger}" style="float: left;" >
                <f:selectItems value="#{birimMBean.birimler}" var="birim" itemLabel="#{birim.birim_adi}" itemValue="#{birim.birim_id}" />
                <p:ajax event="change" listener="#{birimMBean.processAjaxBehavior}" />        
            </p:selectOneMenu>
            <br/><br/>
            <p:selectOneMenu id="bolumu" value="#{bolumMBean.secilenBolum}" style="float: left;">
                <f:selectItems value="#{bolumMBean.bolumler}" var="bolum" itemLabel="#{bolum.bolum_adi}" itemValue="#{bolum.bolum_id}" />
            </p:selectOneMenu>

public void bolumBilgileriniGetir（字节id）{
bolumler=新的ArrayList（）；
Session Session=HibernateUtil.getSessionFactory（）.openSession（）；
Query Query=session.createQuery（“来自Bolum b，其中b.birim.birim_id=：id”）；
query.setParameter（“id”，id）；
bolumler=query.list（）；

}

//yeni_kayit.xhtml关于上述问题

@Override
public void processAjaxBehavior(AjaxBehaviorEvent event) throws AbortProcessingException {
    String birimRequested = deger;
    byte birimId = Byte.parseByte(
    bolumManagedBean.bolumBilgileriniGetir(birimId);
}

public void bolumBilgileriniGetir(byte id) {
    bolumler = new ArrayList<Bolum>();
    Session session = HibernateUtil.getSessionFactory().openSession();

    Query query = session.createQuery("from Bolum b where b.birim.birim_id = :id");
    query.setParameter("id", id);
    bolumler = query.list();

<p:selectOneMenu id="birimi" value="#{birimMBean.deger}" style="float: left;" >
                <f:selectItems value="#{birimMBean.birimler}" var="birim" itemLabel="#{birim.birim_adi}" itemValue="#{birim.birim_id}" />
                <p:ajax event="change" listener="#{birimMBean.processAjaxBehavior}" />        
            </p:selectOneMenu>
            <br/><br/>
            <p:selectOneMenu id="bolumu" value="#{bolumMBean.secilenBolum}" style="float: left;">
                <f:selectItems value="#{bolumMBean.bolumler}" var="bolum" itemLabel="#{bolum.bolum_adi}" itemValue="#{bolum.bolum_id}" />
            </p:selectOneMenu>

将

update=“bolumu”

添加到

p:ajax

标记中。

将

update=“bolumu”

添加到

p:ajax

标记中，请再试一次。感谢您的回答：）我用这个答案解决了我的问题。没问题。我把它作为一个单独的答案加了上去。