XForms

Discovered what appears to be a problem in calculating big decimals (greater than 1,000,000 ). I have a requirement where the total is a sum of all line items.

Each of the $ amounts on the line items is an xs:decimal . The sum is also a decimal. When the sum is greater than 1,000,000, [Orbeon] seems to store the result in an exponential format (e.g. 1.000000E6). This representation is invalid for an xs:decimal (the pink background is a style applied to invalid fields).

I solved the problem by casting the result back into a decimal:
- XPath to the rescue.

Now it looks the way it is desired:

If you want to format a number such as 8988981.00 to look like 8,988,981.00, you would do it like this:

• Works in <xf:input> element too (according to documentation)
• Works only with 'ref' attribute and does not work with 'value'

Use output element for showing images in XForms. Here is how you render an image when you have a URL for an image:

That should render this picture:

DanMcCreary recently blogged about what he terms XRX on http://xml.com . I could not post my comments there, so I will keep them here until I can...

An elegant introduction to an elegant architecture, Dan. Thank you. The essential takeaway from what you describe is the exploitation of XML from one end to the other end - especially from the Developer's perspective, for, how XRX actually manifests in runtime could be left to implementation technologies. Thus the logical architecture of XRX could be realized by a few variations of concrete technology - which is great. The XForms could be realized by XForms server technology (such as the excellent Orbeon stack), the ReST could be realized by any middle tier and the XQuery could be realized by an XQuery engine (such as Data Direct) that may actually be driving any one or a combination of datastores (XML, SQL, file system or ...) . The symmetrical and consistent leverage of XML as a data model from creation to transport to rest and back eliminates a whole lot of wasteful work. Like you point out, XPath is one of the most powerful query systems I have encountered; you can pack so much in so little and reuse it across the board with little if any change from the drawing board to production. In such a system as you describe, a business rule expressed once can be reused anywhere - from one end-to-end , however long the travel, as long as the architecture is XRX, like you have described. Thanks for expressing it so well. A few of your readers will not get it - it is one of those things that once you experience it, you are left wondering why this did not happen before. Oh, well!

helps to cross the chasm with their XForms builder. Thanks to AlexBleasdale for sharing.

Tips
*Passing XML as input to your XForm*
In your XForm:

<xf:instance id="edit-params" src="input:instance"/>

The test.xml looks like this:

The "setValue" tag tells Orbeon to take the user and crvid passed to via the HTTP Querystring like so: &user=john?crvid=19-08-178 and sticks them into the fields.

Figuring these connections out is a nightmare. However, once you figure it out, its nectar.