Re: Updating Multiple Views
On Feb 9, 12:41 pm, "Jason Cavett" <jason.cav...@gmail.com> wrote:
Here's my problem...
I have one Model.
I can have multiple views to that model (depending on how the user
wants to see the information).
Problem: The user can have multiple views to the same model open at
the same time. If the user changes data in one view (which will
update the model), I want it to reflect in the other view(s). I
originally tried this by notifying all observers of the model (which
includes the original view that was just edited) and repopulating the
fields of the views. But, when I fire off the notification, I get
this exception:
Exception in thread "AWT-EventQueue-0 java.lang.IllegalStateException:
Attempt to mutate in notification
...whenever I edit a TextField or anything else with a
DocumentListener.
I sorta understand why this is happening (writeLock() and not being
able to modify while I'm notifying) but I am very confused on how to
fix it. Can anybody give any suggestions?
First, this is more on-topic at comp.lang.java.gui.
Second, your views shouldn't modify any part of the model based while
responding to a change in the model.
If you should implement a single model that represents all
interconnected aspects of your business domain, and have all of your
components able to read values from the model.
Having a model observer modify the model runs the risk of infinit
recursion or infinit loops.
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