[Laszlo-dev] For Review: 20081001-laszlo-a Summary: SWWF8/9 and DHTML: Survey: "Bad Vacation Choice: Trenton" dialog only works the first time

[J Crowley]

I second this.

P T Withington wrote:
> On 2008-10-02, at 02:30EDT, J Crowley wrote:
>
>> Details: Ontext event doesn't get called if
>>   the text is set to the same value as what
>>   was already present.  (Is this a bug, or
>>   is it desired behavior?  If it's a bug,
>>   I'll file it, but I've noticed this for
>>   some time now and just thought it was
>>   expected.)
>
> Darn good question.
>
> I'm sure this behavior is the result of an (over) optimization.  I 
> seem to recall there is some optimization to ignore duplicate sets, 
> probably because the font/size computations that entail, and that 
> there is a special over-ride flag to say 'no, seriously, I want to 
> re-do the set', because if you have changed the font, even though the 
> text is the same, you need the whole computation.
>
> The question here is:  should setting an attribute always cause the 
> corresponding event (even if the value is not changing)?
>
> My vote is yes.
>
> Pro:
>   It's a simple, consistent rule
>   It is the system default for any attribute that does _not_ have a 
> custom setter
>   Listener's may depend on the action, not the value
>
> Con:
>   Inefficient if the listener depends only on the value
>
> ---
>
> We have at least on bug report touching on this area already:
>
> http://jira.openlaszlo.org/jira/browse/LPP-3002
>
> And one of our most popular recurring bugs is custom setters that 
> forget to send the event:
>
> http://jira.openlaszlo.org/jira/browse/LPP-2273
>
> The current system makes it too easy to write a custom setter an 
> forget to send the corresponding event.  I would be in favor of 
> changing the default so that you have to do something extra to write a 
> setter that handles the sending of the event itself.  Simple 
> proposal:  setter in the open tag always sends the event, setter using 
> the <setter> tag has an option to request handling sending of the 
> event itself.
>
>
>