Is EventData really optional for LinkCondition that may have one ?

Emmanuel BEUQUE (ebeuque@pratique.fr)
Tue, 20 Jan 1998 10:13:41 +0100

Hi all,

I have just read again the last WG12 Resolutions and the MHEG-5 standard
and realized that a feature that I thought impossible may rather be
possible.
I'd just like to have the confirmation here.

Suppose a Link that triggers on a LinkCondition that may have an EventData
(EventType ItemSelected for instance).
In this case, can we define a link without any EventData that would trigger
at any time the ItemSelected Event is generated by the EventSource
ListGroup, no matter which item index was just selected ?

I have found nothing in MHEG that would prevent this to be defined but I'd
like to be sure since, as you may know, you sometimes miss something with
MHEG-5 that is not written where you read.

BTW, if this is possible, I don't think any clarification needed but
perhaps a note could prevent any confusion when reading the standard. In
fact, when reading the standard, it seems not obvious to me whether the
EventData attribute is optional because some EventType cannot have an
EventData or the EventData is optional even for other EventTypes.

If the EventData is always optional, I understand the need of the
GetLastEventData action of Recommandation 18 from WG12. In the example
given above, it is very interesting in my opinion to be able to define only
one link and to get the index of the item selected in a variable because
sometimes, you can not expect how many items your ListGroup may contain.

I only missed the first discussions of the MUG (I know I could check the
archives) but I have never seen anything discussed about this
GetLastEventData action to be added. Could it be possible to know in which
area this issue needs further discussion, as stated in the WG12
recommandations ?

BR,
Emmanuel

__________________________________________________________________
Emmanuel BEUQUE mailto:ebeuque@pratique.fr
MediaServ tel: +33 (0) 2 99 64 35 64
Multimedia consultant & developer fax: +33 (0) 2 99 64 36 65