Null value sent by s:link in dataTable

[chawax]

Hi,

I have a problem when using dataTable tag, I think it's a newbie error but I can't find it ...

What I want :
- A list of employees
- A link to go to a detailed page of the employee

To do this, I have this JSF page :

<f:view>
 <div class="section">
 <h:outputText value="Aucun employé" rendered="#{employes != null and employes.rowCount==0}"/>
 <h:dataTable id="employes" value="#{employes}" var="emp" rendered="#{employes.rowCount>0}">
 <h:column>
 <f:facet name="header">ID</f:facet>
 #{emp.id}
 </h:column>
 <h:column>
 <f:facet name="header">Nom</f:facet>
 #{emp.nom}
 </h:column>
 <h:column>
 <f:facet name="header">Prénom</f:facet>
 #{emp.prenom}
 </h:column>
 <h:column>
 <f:facet name="header">Action</f:facet>
 <s:link id="viewEmploye" value="Voir" action="#{employeCrud.selectEmploye(emp)}"/>
 </h:column>
 </h:dataTable>
</div>
</f:view>

Here's the method selectEmploye in component employeCrud (CONVERSATION scope) :

/**
 *
 */
 public void selectEmploye(fr.horoquartz.t4.core.employe.VOEmploye selectedEmploye)
 {
 if (selectedEmploye == null)
 {
 throw new IllegalArgumentException(
 "fr.horoquartz.t4.gui.employe.EmployeCrudActionBean.selectEmploye(fr.horoquartz.t4.core.employe.VOEmploye selectedEmploye) - 'selectedEmploye' can not be null");
 }
 try
 {
 this.handleSelectEmploye(selectedEmploye);
 }
 catch (Throwable th)
 {
 throw new fr.horoquartz.t4.gui.employe.EmployeCrudActionException(
 "Error performing 'fr.horoquartz.t4.gui.employe.EmployeCrudAction.selectEmploye(fr.horoquartz.t4.core.employe.VOEmploye selectedEmploye)' --> " + th,
 th);
 }
 }

The list of employees works, but when I click on the action link to select an employee, the selectedEmploye parameter is null !

What am I doing wrong ?

[smithbstl]

Most likely, you need to place your table inside of an <h:form> so the value is actually submitted.

[christian.bauer]

s:link does NOT submit a form, it does NOT generate a JSF POSTback. Also, selectEmployee(emp) does not work that way, see the documentation re: EL enhancements in Seam. You want to look at the Hotel Booking example in Seam and see how this kind of thing is done.

[chawax]

Well, that's what I did ... In the main.xhtml of Booking example (Seam 1.1.6), there is a <s:link> which works the same way I tried :

<a:outputPanel id="searchResults">
 <div class="section">
 <h:outputText value="No Hotels Found" rendered="#{hotels != null and hotels.rowCount==0}"/>
 <h:dataTable id="hotels" value="#{hotels}" var="hot" rendered="#{hotels.rowCount>0}">
 <h:column>
 <f:facet name="header">Name</f:facet>
 #{hot.name}
 </h:column>
 <h:column>
 <f:facet name="header">Address</f:facet>
 #{hot.address}
 </h:column>
 <h:column>
 <f:facet name="header">City, State</f:facet>
 #{hot.city}, #{hot.state}, #{hot.country}
 </h:column>
 <h:column>
 <f:facet name="header">Zip</f:facet>
 #{hot.zip}
 </h:column>
 <h:column>
 <f:facet name="header">Action</f:facet>
 <s:link id="viewHotel" value="View Hotel" action="#{hotelBooking.selectHotel(hot)}"/>
 </h:column>
 </h:dataTable>
 <s:link value="More results" action="#{hotelSearch.nextPage}" rendered="#{hotelSearch.nextPageAvailable}"/>
 </div>
</a:outputPanel>

[christian.bauer]

1. Use a newer Seam version, no idea if it works with the old one.

2. "hotels" needs to be a @DataModel, see HotelSearchingAction.java

[chawax]

I found where it comes from ...
My employeList seam component, which contains the employees list, was in CONVERSATION scope. So I think that the conversation was ended when running employeCrud component and of course it could not find the employee in the list ;)
I set my employeList component to SESSION scope and now it works better (other errors, but it goes further and this new error has nothing to see)