Re: XML Fragements in widgets

[Reinhard Poetz]

Sylvain Wallez wrote:
Reinhard Poetz wrote:
Sylvain Wallez wrote:
Reinhard Poetz wrote:
I have the need for a widget that contains XML fragments. Those 
fragements should also be streamed as XML and not as strings. How 
can I achieve this? My first (and only) idea is implementing a new 
widget type (XMLWidget). Or are there better solutions?


I've had for months an unfinished and therefore uncommitted XML 
datatype on my hard disk and the associated convertors. Want to 
finish them?

Sounds interesting but I'm not sure if this solves my problem. If I 
have a widget that has the value "<someXML>bla</someXML>" I need it 
serialized as

<fi:field>
  <fi:value>
    <someXML>bla</someXML>
  </fi:value>
</fi:field>
and not as
<fi:field>
  <fi:value>
    &lt;someXML&gt;bla&lt;/someXML&gt;
  </fi:value>
</fi:field>
After looking at Field.generateSAXFragement() (line 405) I don't think 
that a special datatype or a convertor can help here as only the 
string representation of the value is passed to the content handler:

contentHandler.characters(stringValue.toCharArray(), 0, 
stringValue.length());

Therefore my conclusion that I need a special XML widget that can 
produce more than character events, right?

Right. Unfortunate but right.
What's your use case? If it's of general interest, we could add some 
"xml aware" convertors that could produce a SAX stream additionally to a 
string:

interface XMLConvertor extends Convertor {
   convertToXML(Object value, Locale locale, FormatCache cache, 
ContentHandler handler)
}

My usecase is that my backend provides many text snippets and they have to be 
mixed in between widgets. As these snippets are independant of particular 
widgets I can't use fd:hint. On the other hand these snippets relate to the 
state of the forms application and it *could* be more convenient for the 
programmer to deal with the snippets within the forms framework (--> event 
handling).

I'm going to implement it by putting the snippets into separate objects for the 
first. If this becomes clumsy I will fall back to the XMLConvertor idea.

--
Reinhard Pötz           Independent Consultant, Trainer & (IT)-Coach 

{Software Engineering, Open Source, Web Applications, Apache Cocoon}
                                       web(log): http://www.poetz.cc
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