Including a subreport into a GROUPING section

Question

Crystal Reports: including a subreport into a grouping section? asked the same question, but I am hoping a comment on the accepted answer is wrong: that it can't be done because the subreport must be in the details section. Also, what the selected answer says to do isn't working (perhaps because of the other detail, no pun intended).

So this looks like a duplicate question, yet the original question does not appear to be answered, and certainly the accepted "answer" is not usable by me.

(see also How to handle a duplicate question when the original has an accepted answer that is not really acceptable?)

My subreport can list one to many items, each of which can join to one or more items in the main report details. The common field they join on is the grouping item. So, for example, the subreport might have three items and the details five, but if I put it all in the details, I would have fifteen rows, with the first part repeated five times and the second part three times.

The common item appears as a "command field", a "report field". and the Group item. But no matter which of those I link as a subreport parameter, the subreport gets nothing and asks me to enter a value when I try to view the report.

Answer 1

In a more recent version of Crystal Reports you have two options: You can either connect the subreport to a value on the main report via the subreport parameter dialog. or you can pass a Shared Variable between the reports. If you are using the subreport parameter dialog, then the value passed in will be whatever that value is at the time the group is displayed. If the value comes from a detail in that group or from a variable on the main report it shoud pass fine. If the value is something that would be displayed after the group is displayed on the report (going top to bottom) then the value won't be written yet and will be passed to the report as null or blank.

Shared Variables are shared between a report and all of its subreports. If you need to get data from a subreport or pass a single value to multiple subreports, it might be the better option. If the shared variable is changed in the report or a subreport, it'll use the new value in everything after that.

SAP has a good guide on both techniques here: http://scn.sap.com/people/ashish.bamzai/blog/2011/11/23/passing-values-between-reports-crystal-reports-2008

Bear in mind that Crystal Variables are always populated based on their position in the report and the order they are printed in. If something needs to happen after another group or subreport prints, you'll need to use the WhilePrintingRecords keyword.