SetData & ContentRef

Guillaume AUDEON (guillaume.audeon@cril-ing.fr)
Thu, 22 Jan 1998 10:32:47 +0100

Dear MUGers,

I would like to submit to you a problem that I encountered while
developing a "simple Web browser" in MHEG-5.
For all that, I intented to use HyperText objects, GetLastAnchorFired
and SetData actions.
The textual notation would look like:

...
{:HyperText 1
...
:OrigContent :ContentRef ("default.htm")
...
}
{:OStringVar 2
:OrigValue ""
}
{:Link 4
:EventSource 1
:EventType AnchorFired
:LinkEffect (
:GetLastAnchorFired (1 2)
:SetData (1 :NewRefContent (:IndirectRef 2))
)
}
...

This looks simple but unfortunately cannot work. Because
GetLastAnchorFired returns its result in an OctetStringVariable and
SetData takes the new content reference from a ContentRefVariable. And I
have not been able to find a workaround in MHEG-5.
Would you like to be so kind with me as to help me solve this problem?

In addition, I found a solution provided by the DAVIC specifications:
the use of a ResidentProgram, named "CastToContentRef".
Would not it be simplier to extend the SetVariable action to take into
account OctetString <-> ContentRef conversions?
Should not this be addressed by the MHEG-5 Maintainance Task Force?

Very best regards.
Guillaume

-- 
Guillaume AUDEON - CRIL INGENIERIE
5 square du Chene Germain - 35517 CESSON SEVIGNE (France)
+33 2 99 38 43 43 - mailto:guillaume.audeon@cril-ing.fr