Question

I’m trying to pass a parameter between a JSF page to another, from a bean to another. I know it is a common question, infact I’ve tried several approaches before writing it down.
To do that I have put both the beans in session scope and added in the first bean the following:

<p:commandButton value="Submit" type="submit"
    actionListener="#{sourceBean.save}" action="success">

    <f:setPropertyActionListener
            target="#{targetBean.foo}" value="#{sourceBean.foo}" />
</p:commandButton>

The problem is that I don’t want these beans to be in session scope but in view scope.
So I tried to put in my first page:

<p:commandButton value="Submit" type="submit"
    actionListener="#{sourceBean.save}" action="success">
    <f:param name="foo" value="#{sourceBean.foo}"/>                     
</p:commandButton>

And in the second page:

<f:metadata>
<f:viewParam id="foo" name="foo" value="#{targetBean.foo}"
    />
</f:metadata>

The problem is that the passed String is null so, obviously, I get an error form the Converter.

I think I’m missing something in the configuration of my managed beans. Do I have to link target and source bean in someway?
At this moment I have this configuration:

    <managed-bean>
    <managed-bean-name>targetBean</managed-bean-name>
    <managed-bean-class>guiBeans.TargetBean</managed-bean-class>
    <managed-bean-scope>view</managed-bean-scope>
</managed-bean>
<managed-bean>
    <managed-bean-name>sourceBean</managed-bean-name>
    <managed-bean-class>guiBeans.SourceBean</managed-bean-class>
    <managed-bean-scope>view</managed-bean-scope>
</managed-bean>

Another question: In my app, the value foo.id, that I use during the conversion, is set autonatically by the database when I save the object so when I call:

actionListener="#{sourceBean.save}"

The converter gets the id and turns it into a String (and viceversa, if needed).
So, I wanted to know if in JSF is first called the actionListener or the function that sets the parameters .

Could be this the reason why I get a null String? Thanks a lot.

Answer 1

The <f:param> is evaluated during rendering of the form, not during submitting of the form. Your problem suggests that the #{sourceBean.foo} value is only been set during submitting the form and thus not available during rendering of the form.

You’d basically need to replace action="success" by action="#{bean.action}" with

public String action() {
    return "success?foo=" + foo.getId();
}

Or, if you’re using navigation cases

<navigation-case>
    <from-outcome>success</from-outcome>
    <to-view-id>/some.xhtml</to-view-id>
    <redirect>
        <view-param>
            <name>foo</name>
            <value>#{sourceBean.foo.id}</value>
        </view-param>
    </redirect>
</navigation-case>

---

Unrelated to the concrete problem, the <f:param> doesn’t support the converter attribute at all. You’d have to access the desired property directly (which is id in the above example).