JSF添加 <f:param> 到数据表

Question

ok I am trying to use the f:param here to pass the requestid as parameter to the review page. Currently am doing it as shown below but managedproperty is not working as I want because I need to post again from review.xhtml. How can i add this f:param tag and then handle it in bean?

    <p:dataTable style="width:50px;" id="requestList" value="#
            {requestBean.requestsList}" var="requestClass">  
            <p:column>  
                <f:facet name="header">  
                    <h:outputText value="ID" />  
                </f:facet> 
                 <a href="review.xhtml?id=#{requestClass.requestID}">
                    <h:outputText value="#{requestClass.requestID}" />  
                 </a>

            </p:column>  

            <p:column>  
                <f:facet name="header">  
                    <h:outputText value="Status" />  
                </f:facet>  
                <h:outputText value="#{requestClass.requestStatus}" />  
            </p:column>  

              <p:column>  
                <f:facet name="header">  
                    <h:outputText value="Details" />  
                </f:facet>  
                  <h:outputText value="#{requestClass.requestTitle}" />  
            </p:column>
        </p:dataTable>  

Thanks

Answer 1

I think you can try the following:

. Keep your bean as RequestScoped and put a hidden field in your form in review.xhtml to contain the id:

<h:form>
   ...
   <h:inputHidden id="id" value="#{mrBean.id}" />
   ...
</h:form>

@ManagedBean(name = "mrBean")
@RequestScoped
public class MrBean {
   @ManagedProperty(value = "#{param.id}")
   private String id;
}

. Keep your bean as RequestScoped and put a <f:param> inside the commandButton in review.xhtml:

<h:form>
   ...
   <h:commandButton value="Submit">
      <f:param name="id" value="#{param.id)" />
   </h:commandButton>
</h:form>

. Change you bean to ViewScoped

@ManagedBean(name = "mrBean")
@ViewScoped
public class MrBean {
   private String id;

   @PostConstruct
   public void prepareReview() {
       HttpServletRequest request = (HttpServletRequest) FacesContext.getCurrentInstance().getExternalContext().getRequest();
       id = request.getParameter("id");
   }
}

Answer 2

JSF

<p:column>  
    <f:facet name="header">  
        <h:outputText value="ID" />  
    </f:facet>
    <h:outputLink value="review.xhtml">
        <f:param name="myId" value="#{requestClass.requestID}" />
            <h:outputText value="#{requestClass.requestID}" />
    </h:outputLink>
</p:column> 

BEAN

Map<String, String> params = FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap();
int requestID = Integer.parseInt(params.get("myId"));

Answer 3

Tables don't have f:params. They can however have f:attributes.

Answer 4

Use ah:outputLink or h:link with a nested f:param like in Edze's answer.

But then on review.xhtml, use an f:viewParam with name="myId" and a value binding to the backing bean of review.xhtml.

f:viewParam is a stateful component and will remember the value between subsequent requests, even if your backing bean is request scoped. An additional advantage is that with f:viewParam you can use normal JSF validators.

Google for BalusC's "communication in JSF 2" article for some examles.