PLUS attributes in a Bridge Panel with XMP SDK

Question

Hi all,
I' m developing a Bridge Info Panel with Flash Builder 4 and XMP SDK.
I have to build a panel that contains the "Model Release Status" metadata.
This metadata belongs to the PLUS Namespace.
This is my form item:
<!-- Model Release Status -->
     <fi:XMPFormItem
          label="$$$/xmp/sdk/custompanels/MySample/ModelRS=Model Release Status:"
          labelTooltip="$$$/xmp/sdk/custompanels/MySample/ModelRST=Summarizes the availability and scope of model releases authorizing usage of the likenesses of persons appearing in the photograph.">
          <fi:XMPComboBox xmpPath="plus:ModelReleaseStatus">
               <fi:XMPComboBoxItem label="$$$/xmp/sdk/custompanels/MySample/ModelRST/None=None" xmpValue="http://ns.useplus.org/ldf/vocab/MR-NON">
               </fi:XMPComboBoxItem>
               <fi:XMPComboBoxItem label="$$$/xmp/sdk/custompanels/MySample/ModelRST/NAP=Not Applicable" xmpValue="http://ns.useplus.org/ldf/vocab/MR-NAP">
               </fi:XMPComboBoxItem>
          </fi:XMPComboBox>     
     </fi:XMPFormItem>
But I see a little difference from the original one.
If I write metadata with Adobe Bridge original panel, I see this:
     <rdf:Description rdf:about=""
            xmlns:plus_1_="http://ns.useplus.org/ldf/xmp/1.0/">
         <plus_1_:ModelReleaseStatus>http://ns.useplus.org/ldf/vocab/MR-NON</plus_1_:ModelReleaseStatus>
         <plus_1_:Version>1.2.0</plus_1_:Version>
      </rdf:Description>
Instead, in my custom panel, I see this.
       <rdf:Description rdf:about=""
            xmlns:plus_1_="http://ns.useplus.org/ldf/xmp/1.0/">
         <plus_1_:ModelReleaseStatus>http://ns.useplus.org/ldf/vocab/MR-NAP</plus_1_:ModelReleaseStatus>
      </rdf:Description>
The Version attribute doesn't compare in my.
I have two questions:
1. is it mandatory this attribute?
In http://ns.useplus.org/LDF/ldf-XMPSpecification they says that is only used in case of misunderstanding.
2. If yes, how can I implement this?
With an event on the save button?
I believe it's more difficult and it's not so useful..
Any idea, guys?
Regards,

Answer 1

Hi,
to answer your questions.
1. As far as I know, the plus:Version is not mandatory.
2. I used the following algorithm in "FileInfo". A hidden XMPTextInput field at the end of the form contains the version.
On the xmpWrite event, I check if the XMP packet has been modified and contains any plus:* values.
In that case I add the version only if at least one plus property is contained in the packet, otherwise it is removed.
Hope this helps,
-- Stefan