JSF 2 composite component, passing attributes to backing bean

Question

I'm stuck on simple JSF2 question:

XHTML:

<xvf:simpleOut identifier="12345"/>

Composite component is supposed to pass "12345" to backing bean and do some output:

<composite:interface>
    <composite:attribute name="identifier" required="true" type="java.lang.String"/>
</composite:interface>

<composite:implementation>
    <!--@elvariable id="arg" type="java.lang.String"-->
    <ui:param name="arg" value="#{cc.attrs.identifier}"/>
    <h:outputText value="#{myBean.getTestOutput('???????')}"/>
</composite:implementation>

How do I pass identifier value, '12345' in my case, to bean's getTestOutput(String arg) method?

Abercromby

Answer 1

You don't need the <ui:param> tag at all. This should work:

<h:outputText value="#{myBean.getTestOutput(cc.attrs.identifier)}"/>

But it might a a good idea to pass myBean through the interface as well rather than refering to it directly, since it would make the composite component reusable.

Cabral

Thanks, you've saved my day! It's new to me that cc.attrs.*, unlike elvariables, can be passed to backing beans. – Abercromby

@Osw: I'm not sure what you mean by "unlike elvariables". If a variable can be resolved by an EL Resolver, it can be passed to a method - if your JSF container supports method parameters in EL expression, which is only available in EL 2.2. – Cabral

you're right. My fault is that I've used nested el expressions like '#{myBean.getTestOutput(#{arg})}'. Thanks again. – Abercromby