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From Andrus Adamchik <and...@objectstyle.org>
Subject Re: Remote Change Notifications
Date Mon, 18 Aug 2014 20:18:45 GMT
It’s been a while since I used it, so I may have the details wrong, but.. DataContext fires
an event whenever it merges snapshot changes coming from its parent. The original cause of
the event may be a peer context commit in the same VM or in a different VM. It works the same..
So you might do this:

context.getEventManager().addListener(
          myListener, 
          “someMethod”, 
          GraphEvent.class, 
          DataChannel.GRAPH_CHANGED_SUBJECT,
          context);

“someMethod” of your listener must take GraphEvent argument. E.g.:

   public void someMethod(GraphEvent e) { /* update UI */ }

Andrus

On Aug 18, 2014, at 8:11 PM, dollj@xsinet.co.za wrote:

> Thanks Andrus
> 
> Say now I want to update my GUI when a change occurs, how do I know that an object has
been updated ?
> 
> regards
> Jurgen
> 
> 
> -----Original Message----- From: Andrus Adamchik
> Sent: Monday, August 18, 2014 1:52 PM
> To: user@cayenne.apache.org
> Subject: Re: Remote Change Notifications
> 
> When you enable remote notifications, Cayenne send and listens to events itself. The
are object commit events to be sure, containing change deltas. When an event is received,
it is processed by the DataDomain, with the result being that all its  contexts update their
copies of objects from the event data.
> 
> Andrus
> 
> 
> On Aug 18, 2014, at 10:50 AM, dollj@xsinet.co.za wrote:
>> Hi All
>> 
>> If you have “Remote Change Notifications” enabled (using JavaGroups, JMS, etc.),
how does Cayenne let you know when a change has been received ?
>> Or how does one listen for these changes / notifications ?
>> 
>> Thanks, regards
>> Jurgen
> 
> 


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