Hi Emmanuel, thanks for the detailed answer !
So 'dynamic' is more or less the short version of 'dynamically calculated representation depending on the current data'. Anyway, impleneting XFA signature brings a fairly portion of work. But if there are 'magic' numbers involved, I wouldn't be too eager to spend time and effort on XFA signatures ... Greetings Andreas ----- original Nachricht -------- Betreff: Re: [iText-questions] Xfa signature Gesendet: Mi, 13. Jul 2011 Von: Emmanuel Coste<rnd...@gmail.com> > You can find a definition of dynamic form in the XFA spec: > > Here is an extract: > > "Dynamic forms change in appearance in response to changes in the data. > They > can do this in several ways. > Forms may be designed to change structure to accommodate changes in the > structure of the data > supplied to the form. For example, a page of the form may be omitted if > there is no data for it. Alternatively > changes can occur at a lower level. For example, a field may occupy a > variable amount of space on the > page, resizing itself to efficiently hold its content. Dynamic forms use > paper or screen real estate efficiently > and present a cleaner, more modern look than static forms. On the other > hand > a dynamic form cannot rely > on a PDF representation of its boilerplate, because the positioning and > layout of the boilerplate change as > the fields grow and shrink or as subforms are omitted and included. Hence > dynamic forms require that the > boilerplate be included in the template in a form that the XFA processor > can > render at run-time. This > rendering does not have the exquisite control over appearance that PDF > yields. Furthermore it uses more > CPU time than a static XFAF form." > > What you say about signature mechanism is correct -- typically an author > signature followed by recipient ones. This principle does not change for > the > XFA documents. > > But Acrobat Pro brings something new, undocumented (well... as far as I > know > of course): the checksum computation written in the XFA form in the > "<form>" > node. > > For example, this node was created by Acrobat Pro (and is *MANDATORY* for > signature validation): > > <form xmlns="http://www.xfa.org/schema/xfa-form/2.8/"; > checksum="OI0a7q2Hu8kYSJ6C19+SSW2F9XI="> > <subform name="formulaire1"> > <instanceManager name="_"/> > <subform> > <field name="Signature1" access="readOnly"/> > <field name="Signature2" access="readOnly"/> > </subform> > <pageSet> > <pageArea name="Page1"/> > </pageSet> > </subform> > </form> > > > > -- > View this message in context: > http://itext-general.2136553.n4.nabble.com/Xfa-signature-tp2172306p3665243.h > tml > Sent from the iText - General mailing list archive at Nabble.com. > > ---------------------------------------------------------------------------- > -- > AppSumo Presents a FREE Video for the SourceForge Community by Eric > Ries, the creator of the Lean Startup Methodology on "Lean Startup > Secrets Revealed." This video shows you how to validate your ideas, > optimize your ideas and identify your business strategy. > http://p.sf.net/sfu/appsumosfdev2dev > _______________________________________________ > iText-questions mailing list > iText-questions@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/itext-questions > > iText(R) is a registered trademark of 1T3XT BVBA. > Many questions posted to this list can (and will) be answered with a > reference to the iText book: http://www.itextpdf.com/book/ > Please check the keywords list before you ask for examples: > http://itextpdf.com/themes/keywords.php > --- original Nachricht Ende ---- ------------------------------------------------------------------------------ AppSumo Presents a FREE Video for the SourceForge Community by Eric Ries, the creator of the Lean Startup Methodology on "Lean Startup Secrets Revealed." This video shows you how to validate your ideas, optimize your ideas and identify your business strategy. http://p.sf.net/sfu/appsumosfdev2dev _______________________________________________ iText-questions mailing list iText-questions@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/itext-questions iText(R) is a registered trademark of 1T3XT BVBA. Many questions posted to this list can (and will) be answered with a reference to the iText book: http://www.itextpdf.com/book/ Please check the keywords list before you ask for examples: http://itextpdf.com/themes/keywords.php
