- From: Adam Bergkvist <adam.bergkvist@ericsson.com>
- Date: Wed, 7 Mar 2012 14:55:00 +0100
- To: Rich Tibbett <richt@opera.com>
- CC: Harald Alvestrand <harald@alvestrand.no>, Travis Leithead <travis.leithead@microsoft.com>, Anant Narayanan <anant@mozilla.com>, "public-media-capture@w3.org" <public-media-capture@w3.org>
On 03/07/2012 01:44 PM, Rich Tibbett wrote: > Harald Alvestrand wrote: >> Q1: Could someone point me at a good description of how events work, and >> where their definition lives? > > http://www.w3.org/TR/dom/#events > >> >> Q2: This style would create an object that represents "the head of the >> MediaStream". Would it be logical to move some of the manipulation >> functions we've been thinking of for MediaStreams onto that object, if >> this is adopted? > > You probably want such functions on the MediaStream object directly. > Assuming you're obtaining secondary use of a MediaStream object (i.e. > you didn't obtain the MediaStream via your own EventListener) then you > can still apply these methods to that secondary object directly. > I agree. And if some functionality only applies to streams that have been acquired via getUserMedia() we have the LocalMediaStream interface for that. >>> I understand that there are some general concerns with this design due >>> to early existing implementations of the callback approach. >>> Specifically, Rich and someone from Google should reply with their >>> thoughts. > > Right. We released navigator.getUserMedia in Opera Mobile 12 in to the > hands of multi-millions of users so this is not a trivial argument at all. > Are you planning to use a vendor prefix for PeerConnection and friends? >>>> examples include XHR and IndexedDB. Events are more flexible than >>>> callbacks >>>> as they allow multiple listeners, chaining, and bubbling; none of >>>> which are >>>> supported by a single callback (as currently specified in the >>>> specification). Some applications will not need the flexibility >>>> provided by >>>> Events, but it is trivial to emulate a single callback system built >>>> on top >>>> of events and is also a common idiom for web APIs: > > Perhaps you could provide concrete use cases where multiple listeners, > chaining and bubbling make it essential that we revisit the callbacks vs > events discussion. > I may have missed something here, but to me, bubbling makes sense for objects in the DOM tree. Since this is a pure JavaScript object I can't see how it would be used. /Adam
Received on Wednesday, 7 March 2012 14:00:51 UTC