[TYPO3-mvc] Extbase / Fluid Form Viewhelper: Only want to change one property of object

[g4-lisz at tonarchiv.ch]

Hi there,

I have a object 'Demand' with a lot of properties, e.g.  string 'fulltext' and integer 'ordering'.

Now there is a form where I want to change just one of it's properties (others of them have been set in an earlier step):

     <f:form name="demand" object="{demand}" action="...">
         <f.form.hidden property="ordering" value="1">
     </f:form>

If i do so, all other properties are lost. If i want to keep another property 'fulletxt', i have to put it in a hidden field, too:

     <f:form name="demand" object="{demand}" action="...">
         <f.form.hidden property="fulltext">
         <f.form.hidden property="ordering" value="1">
     </f:form>

Because I have a lot of properties and because I don't know which one of them are set, a had to put a whole bunch of hidden 
properties in the form. This is quite impractical.

Is there a way to tell the form handler that it should keep all properties, without explicitly listing every property?

Cheers,
Till