[Laszlo-user] High-level design questions

[Yang Zhang]

I'm trying to create the following GUI for managing an object database:

- there are three columns

- left contains a textbox atop a long listbox of objects; the textbox 
filters the objects in the listbox

- middle contains rows of [label: textbox] for editing fields of the 
object selected in the left column

- some of these fields are references to other objects, so the right 
column contains another textbox + listbox (for choosing object to ref)

I'm not sure what the best approach is to implementing this in OL. Some 
specific questions:

- How do I set one component's (the middle column's) datapath to point 
to the item selected by a list component (the left column)? Is there a 
snippet of code I can refer to?

- The textbox atop each listbox is for filtering the list down (e.g. by 
prefix match). What's the best way to implement such filtering? The 
supported XPath isn't sufficient, since it only allows full equality 
predicate.

- The right column should only list objects that are valid for the field 
in question. (E.g., when choosing `authors` of a `publication`, only 
`person` objects should be listed.) Assuming I have a schema like the 
following, what's the easiest way to do this?

<objects>
   <object id="1">
     <field name="class">person</field>
     <field name="name">John Smith</field>
   </object>
   <object id="2">
     <field name="class">person</field>
     <field name="name">Jane Doe</field>
   </object>
   <object id="3">
     <field name="class">publication</field>
     <field name="authors">1</field>
     <field name="authors">2</field>
   </object>
</objects>

- Are there any example applications out there that are (like this one) 
heavily data-bound, and to data of non-trivial structure? I've been 
studying the applications in the OL distribution but they don't seem to 
fit this description.

Thanks in advance for any answers!