How to get BPM Payload attribute value in ADF TaskFlow

Question

Hi,
           Activities which I did : I have created ADF Project. Then I created ADF TaskFlow through 'ADF TaskFlow Based on Human Task' option by locating BPM task. So now TaskFlow is been generated and also respective dataControl value also generated. In TaskFlow I created new .jspx file. I am going to design this jspx page by drag and drop from VO instances from dataControl. So for this jspx page, at runtime value will be populated from DB Table.
                  My Requirement :  When the Flow initiated, there will be Parameter value passed to the TaskFlow through Payload which is available in DataControl. So now I based on the Payload parameter value I need to filter DBTable and show the respective value in jspx page which I created in TaskFlow. So getting Payload value and applying filter on VO based on Payload parameter value has to be done before rendering Page.
I tried to achieve this schenario as like below :
       - Assume like there is attribute called 'transactionId', for which value will be passed to the TaskFlow through DataControl. I created VO based on EO and appended where clause as : "VO.Trans_Id = : bindVar". Created bindVariable called 'bindVar'. In jspx page I just Drag and Dropped VO instance as form. And also I drag and Dropped 'transactionId' as outputText from Payload. And also I created ExecuteWithParams in Binding section of PageDef and mapped that one with invokeAction item in executable section. So now both payload Iterator and invokeAction  will be created in PageDef. I kept Iterator as in the order of : PayloadIterator at first and InvokeAction second one, So that at runtime it will execute in that order. And also I given "refresh" property to payloadIterator and invokeAction to 'renderModel' and I mapped PayloadIterator id to  refreshAfter property of InvokeAction iterator. Now at runtime, So at runtime updated/Newvalue will be retrived to Payload attribute by executing payloaditerator. So now for 'transactionId' value vill be retrieved. Next invokeAction will take value from newly retrieved 'transactionId' as input and execute query. So now VO will be filtered and need to be shown. But instead of that getting error saying like 'No outcome metadata specified for method call activity 'null'.'
Is this way is correct? If yes, then What mistake which I have done?
Is any other way to acieve this schenario?
Do the needful.
Thanks with Regards,
PraveenKumar.N

Answer 1

Guessing you might have looked at this at some point, but you might want to consider using the setCurrentRowWithKeyValue method to do this.
Here's a blog post that I wrote a while back that goes through step-by-step what I think you're trying to accomplish:  Using a BPM Process Variable on an ADF form to Retrieve Database Information | AVIO Consulting
Hope this helps,
Dan