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Re: Sort out active state spec inconsistencies

From: Adam Bergkvist <adam.bergkvist@ericsson.com>
Date: Tue, 24 Nov 2015 08:33:16 +0000
To: Peter Thatcher <pthatcher@google.com>
CC: "public-media-capture@w3.org" <public-media-capture@w3.org>
Message-ID: <A222C88B6882744D8D4B9681B315889025DCEA89@ESESSMB307.ericsson.se>
I wouldn't mind going down the path of #3 since it would indeed simplify 
things to get rid of the double events. I wonder how much code we would 
break (besides browser layout tests).


On 2015-11-23 23:18, Peter Thatcher wrote:
> I like #3.  It simplifies.  The JS can get to the information it needs
> and doesn't need it to be duplicated in a complex way.
> On Tue, Nov 17, 2015 at 2:18 AM, Adam Bergkvist
> <adam.bergkvist@ericsson.com <mailto:adam.bergkvist@ericsson.com>> wrote:
>     Hi
>     We have some inconsistencies in the spec regarding the active state.
>     We define active in terms of the stream's track set. In short, if a
>     non-ended track exists, the stream is active, otherwise inactive.
>     The active attribute is specified to return true if the stream is active
>     and false otherwise.
>     We also specify that when a stream goes from active, to inactive, the
>     active attribute should be updated to true and the event fired. This
>     contradicts the other text that defines the attribute in terms of the
>     stream's track set.
>     Possible solutions:
>     1. Just remove the attribute updating part of the event dispatching
>     steps.
>     Since the events are scheduled and fired as a result of sync API calls,
>     we might en up in a situation that an "active" event is fired, but
>     that's not true (anymore).
>     2. Remove the attribute updating part of the event dispatching and use a
>     activitychanged event instead of specific active/inactive events.
>     This way when a scheduled event fires, the script needs to check the
>     attribute manually and react. We never get the "event type" - "attribute
>     value" mismatch.
>     3. Remove the active/inactive events all together.
>     These events are rather unnecessary. They either follow direct
>     manipulation from the script or some other event when the UA has
>     initiated a the result of a change to a stream's track set. For example
>     the add/removetrack events or MediaStreamTrack ended.
>     /Adam
Received on Tuesday, 24 November 2015 08:33:53 UTC

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