Re: Two more issues for the tracker

...And the updated pull request and full document are here:

https://github.com/webscreens/presentation-api/pull/23

http://mfoltzgoogle.github.io/presentation-api/

On Mon, Sep 15, 2014 at 2:46 PM, mark a. foltz <mfoltz@google.com> wrote:

> Hi Anssi,
>
> Thanks for the comments.  Responses inline.
>
> On Mon, Sep 15, 2014 at 7:34 AM, Kostiainen, Anssi <
> anssi.kostiainen@intel.com> wrote:
>
>> Hi MarkFo, Yuri, Anton, All,
>>
>> From [1]:
>>
>> On 10 Sep 2014, at 21:01, mark a. foltz <mfoltz@google.com> wrote:
>>
>> > My colleagues Yuri and Anton have begun prototyping parts of the
>> Presentation API in Chromium and raised the following issues which I don't
>> believe are covered in the current specification.   Listed here and filed
>> in GH.
>> >
>> > (1) Are multiple simultaneous calls permitted to startSession()?  My
>> intuition is "no", but I would like to ask the group if there are any use
>> cases where this is necessary.  If the answer is "yes" it adds some
>> constraints and complexity to the user interface for screen selection in
>> the browser.
>> > https://github.com/webscreens/presentation-api/issues/21
>>
>> You mean that until the promise returned by startSession() has resolved,
>> any subsequent calls to startSession() would do nothing, that is the other
>> promise returned by subsequent calls would not resolved either?
>>
>
> Yes.   Here is an example.  The first call to |startSession()| will ask
> the user to select a screen before resolving p1.  In the meantime the page
> makes another presentation request.
>
> var p1 = startSession(myUrl);
> var p2 = startSession(myUrl2);
>
> Here is what I had in mind:
>
> (1) First call to startSession(myUrl) shows the dialog and returns a
> Promise.
> (2) At this point any further calls to startSession() from within the same
> top level document (i.e., tab) return a Promise that never resolves.
> (3a) If the user accepts the presentation request, the Promise in #1
> resolves with the PresentationSession.
> (3b) If the user rejects the presentation request, the Promise in #1 never
> resolves.
> (4) After (3a) or (3b) happens, calls to startSession() will return a
> Promise that resolves in the normal way (same as #1).
>
> If we allow concurrent calls to startSession() from the same document,
> then we would have to queue them up and it would be a confusing user
> experience to show multiple dialogs (how would they know which content is
> requesting what).
>
> Practically speaking, this is unlikely to happen (at least in Chromium):
> the screen selection dialog is modal, blocking user input to the underlying
> page, and if possible, we will likely require a user gesture to cause the
> invocation of startSession().
>
>
>>
>> Please feel free to provide an example to illustrate what you mean if I
>> did not get this right.
>>
>> All - to provide more context for this, see MarkFo’s recent PR [2]
>> summarized at [3]. The HTML version with the PR is at [4].
>>
>> MarkFo - there are still some traces of requestSession() in the sections
>> 5 and 5.4 in your PR [2].
>>
>
> Thanks for the heads up.  I will be sending a revised PR incorporating
> feedback from you and Jonas [1]
>
> [1]
> http://lists.w3.org/Archives/Public/public-webscreens/2014Sep/0058.html
>
> m.
>
>
>
>>
>> Thanks,
>>
>> -Anssi
>>
>> [1] https://github.com/webscreens/presentation-api/issues/21
>> [2] https://github.com/webscreens/presentation-api/pull/23
>> [3]
>> http://lists.w3.org/Archives/Public/public-webscreens/2014Sep/0031.html
>> [4] http://mfoltzgoogle.github.io/presentation-api/
>>
>>
>>
>