Re: Hide items from list

Hi Frederik,

One easy way is to apply your own notion of relevant to your own data 
using the calculate MIP.

Suppose you organize your data thus:

<instance id="data">
<questions xmlns="">
   <question><prompt>X?</prompt><answer>A</answer></question>
   <question><prompt>Y?</prompt><answer>C</answer></question>
   <question><prompt>Z?</prompt><answer>B</answer></question>
</questions>
</instance>

<instance id="list">
    <entries>
        <entry relevant="true" value="A">Choice 1</entry>
        <entry relevant="true" value="B">Choice 2</entry>
        <entry relevant="false" value="C">Choice 3</entry>
   </entries>
</instance>

Then you can create a bind that decides how to set the relevant attributes 
of all the entries or of a particular entry, like this:

<bind nodeset="instance('list')/entry[3]/@relevant" 
calculate="choose(instance('data')/Y/answer = 'B', 'true', 'false')"/>

This makes the third entry of the list have an attribute value that is 
based on how question Y was answered. 
Now suppose the list is used to help drive the answer to question Z.

You can then leverage your attribute in the itemset's nodeset selector, 
like this:

<select1 ref="question[3]/answer">
   <label ref="../prompt"/>
   <itemset nodeset="instance('list')/entry[@relevant='true']">
      <label ref="."/>
      <value ref="@value"/>
   </itemset>
</select1>

As a final note, please understand that this would be your own *notion* of 
relevant, not to be confused with the relevant model item property.  I 
could have just as easily called it "visible" or "show" because it's just 
an attribute name that helps to show or hide certain itemset items based 
on conditions in the data.

Hope this helps.

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





Frederik Elwert <felwert@uni-bremen.de> 
Sent by: www-forms-request@w3.org
10/25/2007 09:28 AM

To
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Subject
Hide items from list







Hello!

In a survey application based on XForms, I want to implement filtering
of pages, questions and question items. For pages (which are just
xf:groups) and questions (which are form controls), this is easily
possible with @relevant.

But how can I filter, i.e. hide, xf:items from xf:select and xf:select1
controls?

E.g., there is one question (xf:select1), "Do you have a dog?" with yes
or no as possible anwers. Now, there's another question (xf:select)
"What do you do in your leisure time?" with "reading", "swimming" and
"play with my dog" as possible answers. Now I would of course want the
last answer only to be visible when the answer to the first question is
"yes".

Any help is appreciated.

Regards,
Frederik