Re: [presentation-api] Allow page to designate a default presentation URL

The |defaultsessionstart| event should only be fired on the top level
frame/document in a given page. If there are multiple <frames> declaring
default presentations, there is no easy way for the user agent to
disambiguate the user intent to initiate presentation.

If the |defaultsessionstart| event handler is attached to the |navigator|
object, how do we ensure that only the frame that declared the <link> tags
gets access the session?

m.


On Mon, Mar 9, 2015 at 7:22 AM, Anton Vayvod via GitHub <sysbot+gh@w3.org>
wrote:

> Hey everyone,
>
> as I'd like to implement this bit of the API in Chrome, I'd like to
> try to get a consensus on the thread [1] and add the result to the
> spec if possible. As I see it, the viable extra specification would
> consist of two parts:
>
> 1) <link rel="presentation-url" href="..."/> and <link
> rel="presentation-id" href="..."/> to allow the page to define and
> change the default presentation URL and id to be used by the UA in the
>  UA-initiated-session scenario; basically any external user action
> that might start a presentation (e.g. clicking the present button in
> UA toolbar, tapping on an NFC tag, etc) would be equivalent to the
> page calling startSession(presentationUrl, presentationId) with the
> values from the <link> tags.
>
> 2) Upon successful connection and session initialization,
> |navigator.presentation.defaultsessionstart| event would be fired by
> the UA to all pages with the matching <presentation-url,
> presentation-id> pair containing the PresentationSession object
> allowing the page to communicate with the initiated session:
>
> [
>     Constructor(DOMString type, optional DefaultSessionStartEventInit
> eventInitDict)
> ] interface DefaultSessionStartEvent : Event {
>     readonly attribute PresentationSession session;
> };
>
> Thoughts?
>
> Thanks,
> Anton.
>
> [1] This was discussed in November last year, see
> http://lists.w3.org/Archives/Public/public-webscreens/2014Nov/0007.html
>
> --
> GitHub Notif of comment by avayvod
> See
> https://github.com/w3c/presentation-api/issues/26#issuecomment-77861764
>
>
>