Empty List on Load in Constellation Landing page

@MarcCheong You mentioned the pyQueryPage is available when you use Promoted Filters on a list Landing page and a data page that is soruced with a data transform or an activity. I have tried to achieve this but haven’t succeeded yet. I have tried on Pega 24.1 and 25.1. I hope you can help me out.

In my use case I have a list data page that is sources via a report definition. The report definition is of a different class than my data page. The report definition uses grouping and display top ranked functionality to return 1 result per group. Via the response data transform everything is mapped accordingly to the datamodel of the data page. This works on a List landing page with promoted filters. However as I do not have the option “Allow querying any column” the promoted filters work on the data returned on the initial retrieval.

Preferably I want to use the values of the promoted filters as filters on my report definition to influence the group by top ranked result. My idea was to create a wrapper data page with a data transform. This data page has the “Allow querying any column” ticked. I create new datapage sourced by a report definition similar as the one mentioned earlier but with parameters. These parameters are then used as filters on my report definition. In my wrapper datapage I create logic to read the values on the pyQueryPage and pass these to the parameters of my data page. Unfortunately I am not able to get this to work.

We have created similar logic on a case with the search and select pattern and reading the parameterized pySearchPage. So I know the approach works but I am just not able to get it to work on a list landing page. What am I doing wrong or what am I missing?