[Zope3-Users] Re: Events

[David Johnson]

>> This is probably the approach I will follow, but what if I want my  
>> container objects notified?
>
> I thought you don't... ?
This is both a theory and practice question.  I want to make sure I  
follow practices that will not lead me into trouble in the future.    
In this case I am likely to want an ObjectModifiedEvent so that my  
objects can be saved if they are modified.  For example if I edit an  
object via browser:editform, an ObjectModifiedEvent will be sent.  I  
am not clear whether Zope will examine every object in my container  
to see if it has an event handler for ObjectModifiedEvent; which is  
what it seems to do now.

>
>> Even if I don't it seems the default Folder implementation follows  
>> this logic and so if you have a folder with several large images  
>> for example, then you will pay a price whenever an event is  
>> issued.  In general it seems that any change will result in the  
>> entire ZODB being read for each event dispatch...if I still follow  
>> the logic here.
>
> That's not what I said. It will only happen on object moves, in  
> particular, when a container is moved. It will also only happen for  
> the subitems of that container, not "the whole ZODB", though  
> arguably that can mean a lot of data.
>
> I would personally like to see some form of disabling event handlers.
Thank you for the clarification.

--
David