RE: improving xforms dispatch

Hi Andy,

You are exactly right that the same use case can be achieved in a different
way, and I think your suggestion of a conditional error handler is the right
way to go. One of the updates to the forthcoming XML Events 2 is indeed a
conditional attribute. This should do exactly what you and Giovanni want.

Regards,

Mark


Mark Birbeck
CEO
x-port.net Ltd.

e: Mark.Birbeck@x-port.net
t: +44 (0) 20 7689 9232
w: http://www.formsPlayer.com/

Download our XForms processor from
http://www.formsPlayer.com/

> -----Original Message-----
> From: www-forms-request@w3.org 
> [mailto:www-forms-request@w3.org] On Behalf Of andyh@collegenet.com
> Sent: 03 December 2004 16:37
> To: Roland Merrick
> Cc: mottagio@libero.it; www-forms@w3.org; www-forms-editor; 
> www-forms-editor-request@w3.org; www-forms-request@w3.org
> Subject: Re: improving xforms dispatch
> 
> 
> 
> 
> 
> 
> 
> Roland,
> 
> I can answer with a similar use case.
> 
> What this request gets to is the ability to take one of a set 
> of actions based on some condition, basically an 
> if/then/else. For example, we have an XForm with a set of 
> <xf:select(1)>'s, but these only appear when relevant, and 
> only when they are relevant to be want to getch the instance 
> data that forms the <xf:itemset>. Now if the user changes 
> their mind and a selection becomes irrelevant and relevant 
> again, I don't really want to go out to the server to fetch 
> that itemset data again.
> 
> That is, I want to get instance data on demand, but I only 
> want to do it the first time, if(count() = 0).
> 
> The request for an XPath expression in @name could achieve 
> this, because you could dispatch to an empty action or a 
> "real" action.
> 
> Now I do have a complicated workaround that involves 
> constraints and form controls in an explicit display:none 
> block, but this is not pretty or elegant.
> 
> Andy
> 
> 
> 
> 
>                                                               
>              
>              Roland Merrick                                   
>              
>              <roland_merrick@u                                
>              
>              k.ibm.com>                                       
>           To 
>              Sent by:                  "mottagio@libero.it"   
>              
>              www-forms-request         <mottagio@libero.it>   
>              
>              @w3.org                                          
>           cc 
>                                        "www-forms-editor"     
>              
>                                        
> <www-forms-editor@w3.org>,          
>              12/03/2004 02:00          
> www-forms-editor-request@w3.org,    
>              AM                        www-forms@w3.org       
>              
>                                                               
>      Subject 
>                                        Re: improving xforms 
> dispatch       
>                                                               
>              
>                                                               
>              
>                                                               
>              
>                                                               
>              
>                                                               
>              
>                                                               
>              
> 
> 
> 
> 
> 
> Greetings, we have a future requirement that might be 
> satisfied by enabling the use of XPath attribute value 
> templates in a number of XForms attributes but not, so far, 
> for @name on the dispatch action. We like to see our 
> requirements more in the form of use cases that cannot 
> presently be addressed, or perhaps the solutions are more 
> difficult than one would like, as opposed to simple requests 
> for additional function.
> 
> Could you articulate a use case that leads you to request 
> that dispatch/@name should allow an XPath expression?
> 
> Regards, Roland
> 
>                                                               
>              
>  "mottagio\@libero\.it"                                       
>              
>  <mottagio@libero.it>                                         
>              
>  Sent by:                                                     
>              
>  www-forms-editor-request@w3.org                              
>           To 
>                                                
> "www-forms-editor"          
>                                                
> <www-forms-editor@w3.org>   
>  03/12/2004 08:52                                             
>           cc 
>                                                               
>              
>                                                               
>      Subject 
>                                                improving 
> xforms dispatch   
>                                                               
>              
>                                                               
>              
>                                                               
>              
>                                                               
>              
>                                                               
>              
>                                                               
>              
>                                                               
>              
> 
> 
> 
> 
> 
> 
> I would like to suggest to the xforms working group to 
> consider the possibility of improving xforms 1.1 schema by 
> accepting in attribute "name" of element "xforms:dispatch" an 
> xpath expression. This will allow programmers more 
> flexibility on construction of dynamic forms, implementing 
> the possibility to dispatch different events depending on 
> instance data values. It seems to me this is a big feature 
> not so difficult to implement. Thank you to everyone that 
> will respond something about. Best regards. Giovanni Motta.
> 
> 
> 
> ____________________________________________________________
> Libero ADSL: 3 mesi gratis e navighi a 1.2 Mega, senza costi 
> di attivazione. Abbonati subito su http://www.libero.it
> 
> 
> 
> 
> 
> 
> 
>

Received on Friday, 3 December 2004 16:53:00 UTC