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RE: onavailablechange event target

From: Oleg Beletski <o.beletski@samsung.com>
Date: Thu, 09 Apr 2015 11:44:17 +0300
To: 'Anton Vayvod' <avayvod@google.com>
Cc: public-secondscreen@w3.org
Message-id: <001d01d072a1$5e8ec3a0$1bac4ae0$%beletski@samsung.com>
Hi Anton,


After some checks I agree that there is no need to use window as an event target. Dispatching event to it might introduce more problems if we decide to support API for workers, e.g. in case of navigator.OnLine [1] events are fired either against Window or WorkerGlobalScope objects.





[1] http://www.w3.org/TR/html51/browsers.html#navigator.online



From: Anton Vayvod [mailto:avayvod@google.com] 
Sent: 02 April 2015 18:18
To: Oleg Beletski
Cc: public-secondscreen@w3.org
Subject: Re: onavailablechange event target


Hi Oleg,


adding any new names to the window object is discouraged as it pollutes the global namespace and can break the existing web sites (see our recent discussion here: [1]).

Hanging an event handler off an object linked to navigator should be fine and is used for example in navigator.connection.onchange: [2].


Hope this helps,



[1] https://github.com/w3c/presentation-api/issues/26#issuecomment-82839960

[2] https://w3c.github.io/netinfo/


On Wed, Mar 25, 2015 at 11:36 AM, Oleg Beletski <o.beletski@samsung.com> wrote:



In Presentation API specification the NavigatorPresentation interface is an EventTarget and is an attribute of the Navigator.


We have noticed that other APIs that provide some data about global state of the Navigator do not use it as an event target because of some reasons. Examples are online/offline events and Gamepad API. There is the navigator.onLine property but events (online, offline) are both dispatched on the Window object. Gamepad API designed in a similar way. Gamepad interface has a attribute "connected" but then events (gamepadconnected, gamepaddisconnected) are fired against the window.


What could be the reason why existing APIs do not use Navigator properties an EventTarget and what the correct way to do that?


Then we also noticed some typos in the working draft in section 7.4 and 8. that mention that events is fired against the PresentationSession (should be the NavigatorPresentation with current design).



Best regards,


Oleg Beletski

Principal Engineer

Samsung Electronics R&D, Finland, Espoo


Received on Thursday, 9 April 2015 08:45:01 UTC

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