Why does #{param.testParam} stop working after a pageDefinition is created?

Question

Hi there,
Environment:
JDeveloper 11.1.1.7
Setup:
I have a task flow with a simple view that takes one input page parameter, namely
  <task-flow-definition id="simpleTaskFlow">
    <view id="view1">
      <page>/my/test/view/myView.jsff</page>
      <input-page-parameter>
        <from-value>#{param.testParam}</from-value>
        <to-value>#{pageFlowScope.testParam}</to-value>
      </input-page-parameter>
    </view>
  </task-flow-definition>
My page fragment /my/test/view/myView.jsff then just simply tries to af:outputText the input parameter:
<?xml version='1.0' encoding='UTF-8'?>
<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="2.1"
          xmlns:af="http://xmlns.oracle.com/adf/faces/rich">
    <af:outputText value="#{pageFlowScope.testParam}" id="ot1"/>
</jsp:root>
Problem
All is good UNTIL I generate a page definition for the page fragment, the input page parameters that I have set fail after this. I think it is a problem with #{param.testParam}.
I can access it via the page definition using a parameter who's value is #{param.testParam}, e.g.
  <parameters>
    <parameter id="testParam" value="#{param.testParam}"/>
  </parameters>
and then use #{bindings.testParam} in my page fragment instead
BUT that I want to avoid, can anyone advise on why this is so? And can I still get #{param.testParam} from a view with a page definition?
Regards

Answer 1

Hi,
this may have to do with the partial data fetching, which basically issues follow-up requests to fetch data. However, a view in a bounded task flow should not read parameters from the request. Instead the task flow should have an input parameter passing this information into the pageflow bean
Frank