Bug 373812

Summary:	Media controls permanently garbled after terminating MPRIS server
Product:	[Plasma] plasmashell	Reporter:	Urs Fleisch <ufleisch>
Component:	System Tray widget	Assignee:	Plasma Bugs List <plasma-bugs-null>
Status:	RESOLVED FIXED
Severity:	normal	CC:	kde, notmart, plasma-bugs-null
Priority:	NOR
Version First Reported In:	5.8.4
Target Milestone:	1.0
Platform:	Arch Linux
OS:	Linux
Latest Commit:	https://commits.kde.org/plasma-workspace/c7dda807318670b1d9ec3cedca116c448ae5c907	Version Fixed/Implemented In:
Sentry Crash Report:

Description Urs Fleisch 2016-12-18 11:29:47 UTC

When an MPRIS server is terminated while the media player controls are open, they will be garbled when an MPRIS server is started again.

Steps to reproduce the bug:

I use audacious here, but the problem occurs also with other MPRIS servers, I discovered it while developing my own MPRIS server.

Applications used: KDE Frameworks 5.29.0, plasma-workspace 5.8.4-1, Qt 5.7.1, audacious 3.8.1 (Arch Linux).

- Start audacious, open some file in it.
- Click on the media control icon in the panel to open it, the current song is displayed (cover art, title, artist).
- Without closing the media player control window, click on the close icon in the window border of audacious (do not focus the audacious window or any other window, the media control window must stay open).
- Start audacious again.
- Hover over the media player icon in the panel, it looks normal.
- Click on the media player icon, the window appears, but it is empty. The panel is messed up, icons and text which should appear in the media control window are drawn on the panel.
- The panel is permanently messed up an unusable until Plasma is restarted e.g. using "killall plasmashell && kstart5 plasmashell".

I suppose that some MPRIS events are not correctly handled when the media control window is open in /usr/share/plasma/plasmoids/org.kde.plasma.mediacontroller/contents/ui/ExpandedRepresentation.qml.

Comment 1 Kai Uwe Broulik 2016-12-18 14:56:04 UTC

Wow. Thanks a lot, I've experienced that bug a couple of times but could never find a reliable way to trigger it.

I think this is rather system tray messing up. When you close the player, the media controller applet is removed (it is dbus-activated and is only loaded when there's an mpris service running). Now, when there's a player again, the applet is loaded again and changes from passive (hidden in the popup) to active (visible in the icon strip) once the async request to the mpris service has finished. This somehow causes it to re-parent the full rep to the wrong container.

Marco?

Comment 2 Kai Uwe Broulik 2016-12-18 14:57:15 UTC

Btw, it can also be triggered with VLC:

- Start VLC and play some song
- Open media controller and keep it open by checking the tick in the corner
- Close VLC
- Start VLC again

-> Media controller is now parented to the compact rep of system tray rather than int he popup

Comment 3 Marco Martin 2016-12-23 16:08:02 UTC

Git commit c7dda807318670b1d9ec3cedca116c448ae5c907 by Marco Martin.
Committed on 23/12/2016 at 16:05.
Pushed by mart into branch 'Plasma/5.8'.

make sure  applet is removed from stack when destroyed

when an applet is deleted, remove its fullrep from stackview before
the applet actaully goes away, as QQC1 StackView remains in an inconsistent
styate if one of its pages is deleted without having been fully removed
reviewed-by: kbroulik

M  +8    -1    applets/systemtray/package/contents/ui/PlasmoidPopupsContainer.qml

https://commits.kde.org/plasma-workspace/c7dda807318670b1d9ec3cedca116c448ae5c907

Comment 4 Urs Fleisch 2016-12-24 10:48:02 UTC

Great, thank you very much for this fast fix! After replacing PlasmoidPopupsContainer.qml and restarting plasmashell the problem is solved.

Comment 5 Kai Uwe Broulik 2016-12-24 11:54:29 UTC

Also thank you for finding a way to reliably reproduce this bug, without it this fix would not have been possible :)