Schema for Handling 'embedded' tags?

Dear list,

I am having a bit of trouble trying to marshal following kind of XML
document:

<text font-weight="normal" fill="blue">
  This text is normal,
    <tspan font-weight="bold" fill="red" >but this is bolded,</tspan>
  while this is normal again.
</text>

Previously, when we did not have to support the embedded <tspan>
element, the following XML-to-Smalltalk binding was ok:

<object name="text" smalltalkClass="MEFloatingTextGO">
  <attribute name="fill" aspect="svgFill" ref="xsd:string"/>
  <attribute name="font-weight" aspect="svgFontWeight"
ref="xsd:string"/>
  <text aspect="svgTextSource" ref="xsd:string" />
</object>

With <tspan> this does not work - the <tspan> part gets neglected during
the marshaling and I get only "This text is normal" and "while this is
normal again." parts. I understand that <tspan> requires its own piece
of schema, but before that I have to figure it out from the rest of the
text somehow. I tried some <element> and <any> variants instead of
<text> but with no luck so far. Any ideas of how to solve the problem or
what to try next?


With best regards,

Risto Pohjonen
MetaCase

I don't really know a solution, but maybe you can achieve what you want
with the
XPath-expressions mentioned in the doc. But i doubt it, because the
<tspan>-element
has its own attributes and therefore must be marshaled to an object and
not a simple
string like the text of the <text>-tag. Maybe you can tell us to what
your example
should be unmarshaled to?

Nevertheless you may consider following strategy:

Try not to directly map the XML to the objects you want to use. Instead
make intermediate
objects which are related 1:1 to the XML-tags. They are used only for
marshaling/demarshaling.
In your case <tspan> would become a new intermediate object. After
reading your XML
you can build your Business objects from your intermediate objects using
all the power of
Smalltalk without any restriction. This has proved useful in the
situation you have to marshal
and demarshal and want to handle errors yourself.

HTH

Volker

Risto Pohjonen wrote:

Volker wrote:

>I don't really know a solution, but maybe you can achieve
>what you want with the XPath-expressions mentioned in the
>doc. But i doubt it, because the <tspan>-element
>has its own attributes and therefore must be marshaled to
>an object and not a simple string like the text of the
><text>-tag.

I checked the XPath-expressions but didn't get too far before it got
confusing :-)

>Maybe you can tell us to what your example should be unmarshaled to?

From the following XML document

<text font-weight="normal" fill="blue">
  This text is normal,
    <tspan font-weight="bold" fill="red" >but this is bolded,</tspan>
  while this is normal again.
</text>

I should get the whole text of "This text is normal, but this is bolded,
while this is normal again" stored (as Text) in an instance variable of
an object and properly handle the <tspan> attributes along the way. I
have advanced so far that I can get the <tspan> part unmarshaled, but
unfortunately that happens separately from the rest of the text and
there is no good way to merge these two.

>Try not to directly map the XML to the objects you want to use.
>Instead make intermediate objects which are related 1:1 to the
XML-tags.

I am not sure if this solution would work, as the trouble seems to
originate from the fact that the <tspan>s are included arbitrary within
the <text>. As I said, I can get both <tspan> and non-<tspan> parts
unmarshaled now, but not at the same pass. Of course there is always
ways to hack around this somehow - and the XPath-expressions seemed to
provide some help on this - but to me the situation appears trivial
enough that one should be able to handle it on XML-to-Smalltalk-binding
level. So, I asked about this directly from Cincom and I am now waiting
for their answer before trying out anything ingenious :-)


Thanks & best regards,

Risto Pohjonen
MetaCase