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Re: xforms:copy binding query

From: Erik Bruchez <ebruchez@orbeon.com>
Date: Wed, 24 Oct 2007 08:39:45 -0700
Message-ID: <471F6741.80005@orbeon.com>
To: www-forms@w3.org

Rob,

That's exactly it! And the discussion on the topic we are having in 
todays Forms WG teleconference seems to confirm that we would like 
xforms:copy to behave like this. If everything goes well, we will 
clarify the spec on this as well.

-Erik

Robert Walpole wrote:
> Erik, John, Aaron,
>  
> Many thanks for your considered responses.
>  
> If I understand correctly, if should be possible to implement 
> xforms:copy (and xforms:value for that matter) in such a way that 
> any elements (or text) from another select control already in the target 
> node are not lost when switching controls - and that this would meet the 
> XForms standard (albeit with a warning to be handled by the implementation)
>  
> I take it that it should also be possible when initiating an XForm 
> pre-populated with data from a database to make these same controls show 
> the appropriate selections based on the nodes that match the items they 
> contain (while ignoring the ones they don't).
>  
> Assuming I have this straight then I will discuss this with my colleague 
> to see if we can acheive this behaviour in Chiba. If so I think my 
> problem is resolved :-)
>  
> Thanks again.
> Rob Walpole
> Devon Portal Developer
> Email robert.walpole@devon.gov.uk <mailto:robert.walpole@devon.gov.uk>
> Web http://www.devonline.gov.uk
>  
>  
> 
> ------------------------------------------------------------------------
> *From:* www-forms-request@w3.org on behalf of Erik Bruchez
> *Sent:* Wed 24/10/2007 00:24
> *To:* www-forms@w3.org
> *Subject:* Re: xforms:copy binding query
> 
> 
> All,
> 
> We had a related discussion during one of the last Forms WG calls
> (John, in case this doesn't ring a bell, this was the rare meeting
> which you did not attend).
> 
> This discussion was not directly related to xforms:copy but to
> xforms:select with xforms:value. Here are the relevant issues for
> XForms 1.1:
> 
>    http://tinyurl.com/2bgvot
>    http://tinyurl.com/2bf4zv
> 
> What we decided during that call was that:
> 
> 1. xforms:select should be non-destructive
> 2. xforms:select should show an out-of-bound condition
> 
> I think that the same behavior should apply to xforms:copy. If so, and
> if I understand your initial issue well, what you want to do should be
> possible if/once implementations follow this non-destructive logic.
> 
> -Erik
> 
> Robert Walpole wrote:
>  > Hi John,
>  >
>  > Thanks for your reply. To avoid any further confusion I will stick to
>  > the real world example of what I am trying to do.
>  >
>  > Basically, I have a target XML node which is a <metadata/> element. On
>  > my form I want to have 2 select controls. One with accessibility options
>  > and one with clientgroup options. Each of these controls is populated
>  > with a different itemset. When the user selects options from the
>  > controls I want the selected items to be placed in the same metadata
>  > target node.
>  >
>  > In other words, if the user selects 2 options from the accessibiliy list
>  > and 2 options from the clientgroup list I want the resulting XML to look
>  > like something like this.
>  >
>  > <metadata>
>  >         <accessibility>1</accessibility>
>  >         <accessibility>2</accessibility>
>  >         <clientgroup>a</clientgroup>
>  >         <clientgroup>b</clientgroup>
>  > </metadata>
>  >
>  > Previously I have attempted to handle this using xforms:select1 within
>  > an xforms:repeat and an associated trigger to add additional form
>  > controls and therefore multiple elements of the same name. However the
>  > more complex the data model the more cumbersome this becomes and so I am
>  > trying to use xforms:copy as a more elegant solution. The problem I am
>  > having with this is that the bindings to the target node appear to be
>  > mutually exclusive and in the implementation I am using (Chiba) I am
>  > physically unable to select items from both lists. I can select multiple
>  > items in one list and then as soon as I start selecting items in the
>  > second list the items in the first list are deselected and do not show
>  > in the submitted data.
>  >
>  > I am not sure what you mean by an "out of range event". I assume that
>  > this is something handled by the implementation? In any event a
>  > colleague of mine has added the xforms:copy functionality to Chiba so it
>  > is possible we may be able to modify the behaviour, if appropriate.
>  >
>  > It may be that the only answer is to change my model so that each select
>  > control has a different target node. The problem with this is that I am
>  > working with a existing dataset and this kind of restructuring is not
>  > desirable.
>  >
>  > Thanks again.
>  > Rob Walpole
>  > Devon Portal Developer
>  > Email robert.walpole@devon.gov.uk
>  > Web http://www.devonline.gov.uk
>  >
>  >
>  > -----Original Message-----
>  > From: John Boyer [mailto:boyerj@ca.ibm.com]
>  > Sent: 23 October 2007 15:31
>  > To: Robert Walpole
>  > Cc: Aaron Reed; www-forms@w3.org; www-forms-request@w3.org
>  > Subject: RE: xforms:copy binding query
>  >
>  >
>  >
>  > Hi Robert,
>  >
>  > It's not clear enough from your first message what you are actually
>  > trying to do. This latest post involving use of insert surely seems to
>  > be going in the wrong direction, though, as the point of copy is that
>  > you don't need generalized insertion capabilities.
>  >
>  > I understood that you wanted two different controls to be able to
>  > contribute to a test data result.
>  >
>  > OK, so that means the ref of the two controls points at the same node
>  > "/test/data"
>  >
>  > But what is the itemset nodeset supposed to point at in the two
>  > different controls?
>  >
>  > Are you thinking to have the two itemsets be different?
>  >
>  > If so, I think it is only slightly problematic.  However, it should be
>  > possible to make it work, and in particular to do so without use of
>  > insert, but there will be a minor hiccup in the fact that each of the
>  > select controls will receive out of range error events for the subtrees
>  > placed in "/test/data" that do not correspond to items in the union of
>  > the item sets but not the complement of their intersection.
>  >
>  > In other words, if you have an item generated by control S1 but not S2,
>  > and you select that item, the subtree will be copied into the node
>  > referenced by S1, but S2 should then receive an out of range event
>  > because it has no item to match that copied node.  But this is a
>  > notification event, which could be ignored or cancelled.
>  >
>  > Finally, perhaps let us know what you really want to do at a higher
>  > level, since a solution other than having two selects with non-identical
>  > item sets might present itself.  But if it is exactly what you need, it
>  > should in principle work, modulo the out of range notifications.
>  >
>  > Cheers,
>  > John M. Boyer, Ph.D.
>  > STSM: Lotus Forms Architect and Researcher
>  > Chair, W3C Forms Working Group
>  > Workplace, Portal and Collaboration Software
>  > IBM Victoria Software Lab
>  > E-Mail: boyerj@ca.ibm.com
>  >
>  > Blog: http://www.ibm.com/developerworks/blogs/page/JohnBoyer
>  >
>  >
>  >
>  >
>  > "Robert Walpole" <robert.walpole@devon.gov.uk>
>  > Sent by: www-forms-request@w3.org
>  > 10/23/2007 04:01 AM To"Aaron Reed" <aaronr@us.ibm.com>,
> <www-forms@w3.org>
>  > cc
>  > SubjectRE: xforms:copy binding query
>  >
>  >
>  >
>  >
>  >
>  >
>  >
>  > Hi Aaron,
>  >
>  > Thanks for your reply. I understand what you are saying about the
>  > bindings although this does seem a bit of a limitation.
>  >
>  > I am interested in your suggestion of using the xforms-select event but
>  > I am struggling to see how this would work.
>  >
>  > At present I am just trying to get it to work with one select control
>  > and I have something like the following:
>  >
>  > <xforms:model>
>  >                 <xforms:instance>
>  >                                  <communitygroup>
>  >                                                   <data/>
>  >                             <metadata/>
>  >            </communitygroup>
>  >      </xforms:instance>
>  >                 <xforms:bind id="data" nodeset="/communitygroup/data"/>
>  >      <xforms:bind id="metadata" nodeset="/communitygroup/metadata"/>
>  >      <xforms:instance id="accessibility-instance"
>  > src="accessibility.xml"/>
>  > </xforms:model>
>  >
>  > <xforms:select bind="data">
>  >                 <xforms:label>Metadata</xforms:label>
>  >                 <xforms:itemset
>  > nodeset="instance('accessibility-instance')/accesstype">
>  >                       <xforms:label ref="accessterm"/>
>  >            <xforms:copy ref="accessibility"/>
>  >            <xforms:action ev:event="xforms-select">
>  >                  <xforms:insert bind="metadata" at="last()"
>  > position="after"/>
>  >                             <xforms:setvalue ref="."/>
>  >                       </xforms:action>
>  >                 </xforms:itemset>
>  > </xforms:select>
>  >
>  > However this produces some pretty mangled results and I'm not at all
>  > sure what the bindings should really look like in this case.
>  >
>  > Any pointers you (or anyone else) can offer would be much appreciated.
>  >
>  > P.S. accessibility.xml attached in case required.
>  >
>  > Many Thanks
>  > Rob Walpole
>  > Devon Portal Developer
>  > Email robert.walpole@devon.gov.uk
>  > Web http://www.devonline.gov.uk
>  >
>  >
>  >
>  >  > -----Original Message-----
>  >  > From: www-forms-request@w3.org
>  >  > [mailto:www-forms-request@w3.org] On Behalf Of Aaron Reed
>  >  > Sent: 19 October 2007 21:53
>  >  > To: www-forms@w3.org
>  >  > Subject: Re: xforms:copy binding query
>  >  >
>  >  >
>  >  >
>  >  > Hi Rob,
>  >  >
>  >  > You can certainly bind two selects/select1s to the same node,
>  >  > but when
>  >  > you select items in a select/select1, it will replace the values
>  >  > underneath it.  The only way you could mix and mingle them
>  >  > are if both
>  >  > selects had the same items and you use ctrl+<click> when
>  >  > selecting items
>  >  > (assuming your process uses a html:select type of control) but then
>  >  > there isn't much reason to have both.  You could always try
>  >  > to manage it
>  >  > yourself with binding the two selects to different nodes and then
>  >  > handling the xforms-select and xforms-deselect events and
>  >  > inserting/deleting the nodes under the 'real' target node yourself.
>  >  >
>  >  > --Aaron
>  >  >
>  >  > Robert Walpole wrote:
>  >  > > Hi,
>  >  > >
>  >  > > I am seeking some clarification about how the XForms copy element
>  >  > > (http://www.w3.org/TR/2007/WD-xforms11-20070222/#ui-adv-copy) should
>  >  > > work.
>  >  > >
>  >  > > My question is whether it should be possible to use xforms:copy on
>  >  > > different xforms:select controls to copy different element
>  >  > nodes into
>  >  > > the same target node?
>  >  > >
>  >  > > For example, say I want to have 2 select controls that use use
>  >  > > xforms:copy to populate the data node in the following...
>  >  > >
>  >  > > <test>
>  >  > >                  <data/>
>  >  > > </test>
>  >  > >
>  >  > > In this case I would bind both of my select controls to the
>  >  > data nodeset
>  >  > > and by selecting two values from both controls I would hope to get
>  >  > > something like the following result...
>  >  > >
>  >  > > <test>
>  >  > >                  <data>
>  >  > >                                   <abc>123</abc>
>  >  > >                                   <abc>456</abc>
>  >  > >                                   <def>321</def>
>  >  > >                                   <def>654</def>
>  >  > >                  </data>
>  >  > > </test>
>  >  > >
>  >  > > Is this allowable? It may be that I cannot bind two
>  >  > different controls
>  >  > > to the same target node. Any clarification of this would be much
>  >  > > appreciated.
>  >  > >
>  >  > > Many Thanks
>  >  > > Rob Walpole
>  >  > > Devon Portal Developer
>  >  > > Email robert.walpole@devon.gov.uk
>  >  > > Web http://www.devonline.gov.uk
>  >  > >
>  >  > >
>  >  > >
>  >  > >
>  >  >
>  >  >
>  >  >
>  >  >
>  >
> 
> 
> --
> Orbeon Forms - Web Forms for the Enterprise Done the Right Way
> http://www.orbeon.com/
> 
> 


-- 
Orbeon Forms - Web Forms for the Enterprise Done the Right Way
http://www.orbeon.com/
Received on Wednesday, 24 October 2007 15:40:01 GMT

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