Question

我想使用p：rating组件来投票并将值保存到数据库中（如果它已被投票以便以后能够从db中提取值）。在实体中我也有注释字段，我想如果已经写了注释只添加投票，所以我有时会进行合并而不是持久化（如果在DB中写入此请求没有任何内容）。我的.xhtml页面中有以下代码：

<h:form
        rendered="#{not empty userRequestBean.request.hiredAgency.city}">
        <p:rating value="#{userRequestBean.rating}" stars="10"
            onRate="#{userRequestBean.rateAgency()}">
        </p:rating>
    </h:form>

在我的豆里，我有：

@ManagedBean(name = "userRequestBean")
@SessionScoped
public class UserRequestBean implements Serializable {
    private Integer rating; // Plus get and set methods
    private TComment agencyComment = new TComment();
    public void rateAgency() {
        if (rating == null) return;
        EntityManager em = HibernateUtil.getEntityManager();
        if (!em.getTransaction().isActive())
            em.getTransaction().begin();
        Query queryAgencyComment = em.createQuery("select comment "
                + "from TRequest req join req.requestComments comment "
                + "where req.id = :requestId ");
        Long requestId = (Long) request.getId();
        queryAgencyComment.setParameter("requestId", requestId);
        agencyComment = (TComment) queryAgencyComment.getSingleResult();

        if (agencyComment.equals(null)) {
            agencyComment = new TComment();
            agencyComment.settRequest(request);
            agencyComment.setCommentDate(new Date());
            agencyComment.setAssessment(rating);
            em.persist(agencyComment);
            em.getTransaction().commit();
        } else {
            agencyComment.setAssessment(5);
            em.merge(agencyComment);
            em.getTransaction().commit();
        }
    }

但是onRate，方法rateAgency不会执行。它只在呈现页面时执行一次。我该如何实现这项工作？

Answer 1

当您尝试运行服务器方法时，属性onRate定义了JavaScript（客户端）操作。你需要一个ajax动作：

<p:rating value="#{userRequestBean.rating}" stars="10" >
    <p:ajax event="rate" listener="#{userRequestBean.rateAgency()}" />
</p:rating>

有用的链接：

PrimeFaces showcase
一个好的JSF教程（如Oracle's Java EE 7 Tutorial）

无法获取PrimeFaces p：rating值并将其保存到Oracle数据库中

1 个答案: