| Hello,
This issue has come up on the list a few times over the years, and I’ve pieced together a workable solution. This post is just to see if anyone can suggest a better one.
I have an ERXWORepetition that loops over the displayedObjects() of a WODisplayGroup. The objects are Job EOs, and within the loop there’s a hyperlink that allows a user to delete the selected Job. (You can see where this is leading.) At some point, users A and B both hit the Jobs list page which displays Jobs J1, J2, J3. User A deletes J1. User B is still on the same list page, and deletes J1—except, obviously, J1 has already been deleted, and the application silently deletes J2 instead.
Setting er.extensions.ERXWORepetition.checkHashCodes=true in Properties and binding the ERXWORepetition’s notFoundMarker to a null-valued variable in the component is a pretty good workaround: now, in the action method, if the item variable is null, I know the selected Job was not found, and I can display an informational message.
Is that the best I can do? In this slightly abridged scenario, the Job got deleted, and that was the only action available, so the informational message can say “The selected Job was already deleted”. But all I really know is that the Job is no longer where it once was in displayedObjects()—right? Say it just got moved by that action method above—is there any way to retrieve J1 when user B hits that method? (I’m not convinced you’d want that in every case, or even many cases, because the selection has been made based on stale data in front of user B. Let’s just consider this a thought experiment.)
|