869020 - The wifi switch remains grayed out when hitting an error upon turning wifi on

Status: RESOLVED FIXED

(Firefox OS Graveyard :: Gaia::Settings, defect)

Description

[Gabriele Svelto [:gsvelto]]

On my Unagi when flipping the wifi switch I see the following error in logcat:

E/GeckoConsole(  425): [JavaScript Error: "NS_ERROR_XPC_CANT_MODIFY_PROP_ON_WN: Cannot modify properties of a WrappedNative" {file: "app://settings.gaiamobile.org/js/wifi.js" line: 51}]

The offending line is visible here:

https://github.com/mozilla-b2g/gaia/blob/master/apps/settings/js/wifi.js#L51

If I understand this correctly the |onerror| property of the |req| object is not being initialized properly preventing the error function to return control over the switch to the user.

To reproduce this issue on my Unagi I did the following:

1. Flash a fresh build (either v1-train or master).
2. Don't add a wifi network in the FTU (none appear to me as wifi is off by default apparently)
3. Go in the settings app, wifi panel
4. Flip the switch

The switch goes into the 'on' position but remains grayed out, no wifi networks appear as wifi is apparently still off. Tapping the switch again at this stage is useless as it will remain grayed out. Killing the settings app and restarting it reveals that wifi remained off and the issue repeats itself.

Restarting my Unagi seems to partially fix the problem; I can still see the error message in the log but now the switch eventually works.

Comment 1

[Gabriele Svelto [:gsvelto]]

Turns out this is caused by misusing the value returned from nsIDOMSettingsManager.createLock() which returns an nsIDOMSettingsLock object and not a DOMRequest one (which would have the |onerror| property).

Comment 2

[Fernando Jiménez Moreno [:ferjm]]

Attachment: Pointer to Github pull request: https://github.com/mozilla-b2g/gaia/pull/9572/files

Pointer to Github pull-request

Comment 3

[Wayne Chang [:wchang]]

Triage 5/8 - leo+ because when the bug is hit, wifi is unusable and recovery is not easy.

Comment 4

[Fernando Jiménez Moreno [:ferjm]]

Comment on attachment 745892 [details]
Pointer to Github pull request: https://github.com/mozilla-b2g/gaia/pull/9572/files

Moving the review to Alive, as he originally reviewed this code in bug 859993

Comment 5

[(inactive after 6/18) Alive Kuo [:alive]]

Comment on attachment 745892 [details]
Pointer to Github pull request: https://github.com/mozilla-b2g/gaia/pull/9572/files

r=me, my previous review failed :/ Thanks!

Comment 6

[Fernando Jiménez Moreno [:ferjm]]

Thanks Alive!

https://github.com/mozilla-b2g/gaia/commit/3f766bccdd9c0961b33f2085089c1f575143bd8b

Comment 7

[John Ford [:jhford] CET/CEST Berlin Time]

Uplifted 3f766bccdd9c0961b33f2085089c1f575143bd8b to:
v1-train: 913769b05882bb4faa448604b7fc6ea2e06c9c2d