Re: Implementors please read: poll about select1 and empty values

(Just found I didn't hit send on this several hours ago).

Yes, absolutely. 

In fact, I ran a slightly larger version of the test, which is a proper 
superset of the one you have below.

I used three items and put the empty one in the middle so I could be sure 
that the item selected on empty string was being selected for that reason 
and not due to some first/last default selection mechanism. 

I also bound both a dropdown and a radio button group to the data node so 
that I could see how different UI presentations of select1 behaved.  In 
particular, our dropdowns don't tend to select stuff in the drop down 
menu, but a radio group obviously does, so there's no doubt about what our 
processor is doing.

Finally, I also added a required="true()" MIP on the "data" node so that I 
could observe the behavior of the controls when the item with empty value 
was selected and deselected.

When my test form comes up, the data value is initially empty, and both 
the dropdown and radio group have the "required but empty countenance.
If I select the first item of the dropdown menu, the non-empty value is 
transmitted to data, and the radio group changes to the first selection. 
Both controls lose the "required but empty" countenance.
If I then select the second item in the dropdown menu, the empty value is 
transmitted to data, and the radio group changes to the second item.  Both 
controls regain the "required but empty" countenance.
The consistent behaviors continue to happen upon selection of the third 
item with a non-empty value and also when I do this whole sequence from 
the radio group and observe what the dropdown shows and does.
That being said, I did also insert an xforms output control bound to the 
data node so I could directly see what it was being set to as well.

Cheers,
John M. Boyer, Ph.D.
Distinguished Engineer, IBM Forms and Smarter Web Applications
IBM Canada Software Lab, Victoria
E-Mail: boyerj@ca.ibm.com 

Blog: http://www.ibm.com/developerworks/blogs/page/JohnBoyer
Blog RSS feed: 
http://www.ibm.com/developerworks/blogs/rss/JohnBoyer?flavor=rssdw





From:
Leigh L Klotz Jr <leigh.klotz@xerox.com>
To:
John Boyer/CanWest/IBM@IBMCA
Cc:
public-forms@w3.org, www-forms@w3.org
Date:
12/09/2010 10:14 AM
Subject:
Re: Implementors please read: poll about select1 and empty values



On 12/09/2010 08:40 AM, John Boyer wrote: 

...
As for answering the implementers poll, the IBM Forms product implements 
the ability of a select1 control to choose an item whose value is empty. 
The emptiness is transmitted to the data node to which the select1 is 
bound.  If that data node is required, then the form control reverts to a 
display state that indicates the user must make a choice. 

John,
Does this mean that IBM Forms allows the first item below to be selected, 
and conversely selects that item if the bound data node is the empty 
string?  That's what my test was intended to find out, and what I believe 
at least some other implementations do.

  <select ref="data">
   <label>data</data>
   <item>
     <label>(None)</label>
     <value />
   </item>
   <item>
     <label>full</label>
     <value>full</value>
   </item>
  </select1/>

Thank you,
Leigh.