1309815 - [Presentation WebAPI] Add a refresh button in device selection prompt

Status: RESOLVED WONTFIX

(Firefox :: Site Permissions, defect, P5)

Description

[C.M.Chang[:chunmin]]

It would be better if there is refresh button to reload the available devices for presentation API in device selection prompt.

Comment 1

[Florian Quèze [:florian]]

Is there any way for the platform to send an event when a new device is detected, so that the UI can be refreshed automatically with the user needing to click a button?

Comment 2

[C.M.Chang[:chunmin]]

(In reply to Florian Quèze [:florian] [:flo] from comment #1)
> Is there any way for the platform to send an event when a new device is
> detected, so that the UI can be refreshed automatically with the user
> needing to click a button?
The Presentation API is based on mDNS, which can't provide event-callback mechanisms in some cases. In that protocol, we need to force update to get the available devices. That's why we need a refresh button.

Comment 3

[Florian Quèze [:florian]]

How expensive is it to force-update? Could we do it every second while the prompt is visible?

Comment 4

[Randell Jesup [:jesup] (needinfo me)]

device-scanning isn't always cheap, though we try to cache it.   Varies by OS considerably, and in some cases perhaps by driver (since we need to interact with the driver to return if a device is available).   We do have a device-change event API now (visible to apps as well)

Comment 5

[Kagami Rosylight [:saschanaz] (they/them)]

Bug 1697680 removed Presentation API implementation.