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Re: Listening for changes on an EO
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Re: Listening for changes on an EO


  • Subject: Re: Listening for changes on an EO
  • From: Chuck Hill <email@hidden>
  • Date: Thu, 9 Jul 2009 12:34:10 -0700


On Jul 9, 2009, at 12:26 PM, Lon Varscsak wrote:

Thanks.  I figured there was nothing built to do exactly what I
needed, but I figured I would ask.

Do you know if there is much overhead if I implemented this in my EO
superclass even if there were no observers?

EOF makes heavy use of notification. I would not expect there to be much overhead. You will probably want to qualify the notification with the EC (depending on what it is you are trying to do) to limit the number of observers. And then keep the method receiving the notification fast. The notifications are synchronous, so you don't want anything slow in this method.



Chuck




-Lon

On Thu, Jul 9, 2009 at 11:50 AM, Simon McLean<email@hidden> wrote:
also, if you are using wonder, check out
hasKeyChangedFromCommittedSnapshot in ERXGenericRecord. maybe listen
for the notification mentioned by chuck, then use
hasKeyChangedFromCommittedSnapshot to check the particular key you are
looking at.


simon

2009/7/9 Chuck Hill <email@hidden>:

On Jul 9, 2009, at 10:24 AM, Lon Varscsak wrote:

Is there a way for a controller object to listen for changes to an EO
(and a specific key)?


Thanks,

Lon

EOEditingContext has ObjectsChangedInEditingContextNotification, but it is
on an object by object basis, not a key by key one.


You could implement this in your EO super class.


Chuck

--
Chuck Hill             Senior Consultant / VP Development

Practical WebObjects - for developers who want to increase their overall
knowledge of WebObjects or who are trying to solve specific problems.
http://www.global-village.net/products/practical_webobjects







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-- Chuck Hill Senior Consultant / VP Development

Practical WebObjects - for developers who want to increase their overall knowledge of WebObjects or who are trying to solve specific problems.
http://www.global-village.net/products/practical_webobjects







_______________________________________________ Do not post admin requests to the list. They will be ignored. Webobjects-dev mailing list (email@hidden) Help/Unsubscribe/Update your Subscription: This email sent to email@hidden
  • Follow-Ups:
    • Re: Listening for changes on an EO
      • From: Lon Varscsak <email@hidden>
References: 
 >Listening for changes on an EO (From: Lon Varscsak <email@hidden>)
 >Re: Listening for changes on an EO (From: Chuck Hill <email@hidden>)
 >Re: Listening for changes on an EO (From: Simon McLean <email@hidden>)
 >Re: Listening for changes on an EO (From: Lon Varscsak <email@hidden>)

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