Hi!
> I am trying to create a master-detail screen scenario and am following the
> best-practices guide in the wiki (the simple CRUD cycle -
> http://wiki.apache.org/myfaces/A_simple_Crud_Cycle) and it does not actually
> work. Am I doing something wrong?
Unhappily the author of this page did not say which scope to use for the
master and detail view.
@Werner, can you comment on it please.
> When I do a save on the DetailView, if I call refreshList on the MasterView
> after saving using the DetailView "instance" of the BO, the list does NOT
> contain my changes. I understand why this is happening. The BO in the
> MasterView has its own entity manager as it is in a different conversation
> than the DetailView. It does not help to do
> Conversation.getCurrentInstance().invalidate() in the DetailView before
> doing a list refresh on the master view as there is still nothing to force
> the entity manager in the MasterView to dump its cached objects.
>
Yep, this invalidate will just invalidate the "detail" conversation, not
the one of the Master.
Some possible ways are:
1) If Master and Detail are both in two different conversations (flash)
simply avoid referencing the Master from your Detail. When navigating to
the Detail this will end the Master conversation automatically, on
navigating back the Master will be a fresh instance with a fresh
EntityManager ... thus, should load the data again.
2) End the Master conversation from within the Detail bean (not
recommended) ConversationUtils.invalidateIfExists("name of master
conversation").
Name of "name of master conversation" is the one you configured using
orchestra:conversationName on the bean definition or the bean-name if
you didn't use that configuration.
3) Use the same conversation for the Master and Detail. Do this by using
the orchestra:conversationName="editXYZData" on both bean definitions.
Then they use the same EntityManager and you are fine anyway. Putting
both in the flash scope will handle the cleanup once the user navigates
away.
This is the way I'll mostly use.
As a side note, if the Master page allows to define some filter, I often
put them into their own bean in a separate conversation of type "manual".
That way, even if the flash conversation ends the user input won't be
lost. For sure, this filter bean should not hold any entity as you might
run into problems if passing entities from one conversation to another one.
Hope this helps!
Ciao,
Mario
