Iterating tags in Seam (ui:repeat and c:forEach)

[Denis Zjukow]

Hello,

Having struggled for a couple of days I finally gave up and decided to ask for help.

I use Seam with Facelets. What I want is to show a list of entities in a table cell i.e a single cell may contain a comma-separted list.

Let's say I have two entity types: Item and Subitem. An instance of type Item may have a number of Subitems. In my case the relation between these two entity types is many-to-many.

So if I have Item1 with three subitems: Subitem1, Subitem2 and Subitem3, I want to see something like this:

<table>
 
  ...
 
  <tr>
 
    ...
 
    <td>Subitem1,SubItem2,Subitem3</td>
 
    ...
 
  </tr>
 
  ...
 
</table>

Please note that I don't want a comma after the last subitem in a cell (Subitem3 in this case). Nothing special, an obvious requierment, isn't it?

The first thing I tried was ui:repeat:

<!-- Table, each row represents an item. -->
<h :mrgreen: ataTable value="items" var="item">
 
  ...
 
  <!-- This is my tricky column. -->
  <h:column>
 
    <!-- I want to see all subitems in a single cell. -->
    <ui:repeat value="#{item.subitems}" var="subitem">
 
      <!-- Show a subitem. -->
      <h :-o	 utputText value="#{item.subItems}" />
 
      <!-- Add separator. -->
      <h :-o	 utputText value="," />
 
    </ui:repeat>
  <h:column>
 
  ...
 
</h :mrgreen: ataTable>

Everything's fine except for the fact that there is a nasty comma after the last subitem. This made me try c:forEach tag:

    ...
 
    <!-- I want to see all subitems in a single cell. -->
    <c:forEach items="#{item.subitems}" var="subitem" varStatus="stat">
 
      <!-- Show a subitem. -->
      <h :-o	 utputText value="#{item.subItems}" />
 
      <!-- Add separator for each subitem except for the last one. -->
      <c:if test="#{!stat.last}">
        <h :-o	 utputText value="," />
      </c:if>
 
    </ui:repeat>
 
    ...

Unfortunately this code won't work! It just leaves my favorite column empty. It seams that c:forEach do not see variable item.
I then tried to find a way to add the conditional logic to ui:repeat, but haven't managed to find anything like c:forEach's 'varStatus'.

Any ideas? Thank you all in advance!

[K Bbb]

you can use <ui:fragment rendered="#{conditional}">

also you could render the 1st item outside the loop, then set the start index to 1 on the loop and then in the loop render the comma first, then the loop item

finaly you can move the code into the java side and don't loop at all..

[K Bbb]

also.. most of the time it doesn't work to mix c: tags with h: tags, c: tags are compile time, h: tags are render time. you can sometimes put an h: tag inside a c: tag, but not the other way.

[Jaikiran Pai]

I guess, the JSF forum is the right place for this question. You might get more answers there. I will move this there for you.

[Mark Spritzler]

"K Bbb",

Great information there, but please change your display name to meet the JavaRanch Naming Policy of using your real first and real last names, thanks

Mark

[Denis Zjukow]

Thank you, K Bbb. I like the idea of conditional rendering. That's exactly what I was looking for.

However, it just seems strange to me that there is nothing like c:forEach among built-in facelet tags. I wish ui:repeat had same functionality as c:forEach, but it unfortunately doesn't.