jsf set ui:param or use a value that changes dynamically in ui:repeat

Question

I want to update an ui:param value or use something similar in ui:repeat loops with a condition. The idea is something as follows (is just an aprox, not the final implementation but I guess is understandable):

<ui:param name="marginLeftNode" value="#{myBean.initialMarginValue}" />

<ui:repeat value="#{myBean.viewWrapper.linkMap.entrySet().toArray()}" var="map">
    <ui:repeat var="link" value="#{map.value}" varStatus="status">

        <li style="margin-left: #{marginLeftNode}%" class="ico-#{link.getStyleCss()}-ayuda">
            <a href="#{link.getUrlLink()}">#{link.getTitle()}</a>
        </li>

        <!-- Code conditions that doesn't works in any way as I've readed in the links after code -->
        <c:if test="#{marginLeftNode gt 4}">
            <ui:param name="marginLeftNode" value="#{myBean.viewWrapper.nodeList.get(status.index).depth}" />
        </c:if>
        <ui:fragment rendered="#{marginLeftNode gt 4}">
            <ui:param name="marginLeftNode" value="#{myBean.viewWrapper.nodeList.get(status.index).depth}" />
        </ui:fragment>
        <!-- End code conditions: these are the two solutions c:if and ui:fragmen I tried -->

    </ui:repeat>
</ui:repeat>

I can't use c:if inside ui:repeat because doesn't works (Specify conditional rendering of element inside <ui:repeat>? The <c:if> does not seem to work) and I can't use ui:fragment with ui:param because it doesn't works too (Conditional variable definition in JSF)

So, any idea how to solve that?

Answer 1

First of all, avoid of use JSTL if you can use JSF. Here is an answer that explains how JSTL and JSF are executed in different steps -> https://stackoverflow.com/a/3343681/4253629

To redefine conditionally a ui:param, for example, you can do this:

<ui:param
    name="marginLeftNode" 
    value="#{marginLeftNode gt 4 ? myBean.viewWrapper.nodeList.get(status.index).depth : marginLeftNode }"/>

Probably exists another solution, but this works.

Greetings