On Thu, 26 Feb 2009 13:25:00 -0800 (PST),
paul.blast.walker@g... wrote:

>I have a fully specified schema against which I can validate my .xml
>files. But given the schema is fully specified, the .xml editing
>should be a multiple choice activity, using the keyboard occasionally
>to enter the field values that would be validated against type. What’s
>more, the validation should be an on going process, such that it would
>be impossible to create an invalid .xml file.

The last requirement you listed is not really feasible.  Unless you
cannot manually type in the content of XML, it will be impossible to
not allow a user to create an invalid XML document.  Most editors do
alert you of errors in some way though.

<...>

>Has anyone found a product that comes anywhere close to my wish list?
>
>The market place is awash with xml editors, there must be one that
>does the job.

I'm currently using oXygen, and I find it to be the best I have used
so far.  If you are familiar with Eclipse, you will be comfortable
using it.  As you type, you can press CTRL-SPACE for a list of
alternatives for documents failing validation.

oXygen's licensing is also the most flexible I've seen.  As long as
you're the sole user (no two installs are running concurrently), they
allow you to install it on as many computers as you wish.