Stream: questionnaire
Topic: calculatedExpression & x-fhir-query?
Paul Lynch (Oct 09 2020 at 13:15):
I think the purpose of allowing x-fhir-query expressions for calculatedExpression was for item type=reference. However, I am not sure how that works. An x-fhir-query will return a Resource (or a Bundle, or the result of an operation), but a Reference is basically a URI with a display string, and not the whole resource the URI points to.
Lloyd McKenzie (Oct 09 2020 at 13:22):
Right, but the drop-down would need to contain information about the referenced resource. The extension we used to use to constrain what is pointed to was a query too
Paul Lynch (Oct 09 2020 at 13:29):
So, then the form renderer needs to construct a Reference from the returned Resource? How does it know what to use for the display string? Or is that up to the renderer?
Lloyd McKenzie (Oct 09 2020 at 13:31):
We provide guidance in the columns extension about what should go in the display. In the absence of that, yes - it would be up to the renderer - or more specifically, the system that captures the response.
Paul Lynch (Oct 09 2020 at 13:45):
The choiceColumn extension controls what goes into the columns of a multi-column drop down list, which would be useful in displaying a list of resources, but I don't see how it controls the format (or the content) of what goes into Reference.display after the user picks an item. Is that just up to the implementation?
Lloyd McKenzie (Oct 09 2020 at 14:40):
There's a property on that extension that indicates if the column value should go in the display
Paul Lynch (Oct 09 2020 at 14:43):
I missed that. That's perfect! Thanks.
Last updated: Apr 12 2022 at 19:14 UTC
