Action Check on multiple selected campaign lines in a workbench screenset

Summary:

How to do Action Check on multiple selected campaign lines in a workbench screenset?

Content (required):

Requirement: When external supplier selects a few campaign lines to generate a consolidated document, according to business logic, not all lines can be printed in one document. Only certain lines having same values on certain fields can be grouped together, e.g. Certifier Type, Start/End Date, etc.

To prevent careless mistake, it is great to have action check when user tries to generate a consolidated document. If any of the required attributes vary among the lines, system should prompt error.

But how can action check check a few records mutually?