I've set up my laptop with a custom SDDM theme and a general Plasma 5 theme (Breeze I think).
I would like to use the SDDM theme for my lock screen, but have failed how to do this. Anyone able to point me to the correct info as how to do it?
Failing this, a workaround would be to "fake" the theme by using a custom lock screen background (even if this still would use the Breeze layout). What size is this custom background image?

Seems you can't do this then?

(disclaimer, I'm using KDE 4, but I assume this didn't change (much) between 4 and 5)

You should be able to set up the theme to use the background from SDDM.
The locker theme is defined by the currently-selected plasma desktop theme. There was a discussion recently on this thread about how to change the locker background for a given theme. You can follow the workaround mentioned to change the background to the SDDM background.

Edit:
Apparently (according to the bug mentioned in that other thread the feature was added for Plasma 5 (specifically 5.2), so presumably you should be able to change the locker background in the locker settings.

That looked promising as there is mention of main.qml in that first thread. So I tried looking for it, but it isn't there. There actually nothing in that directory using Plasma 5. But I found mention of /usr/share/plasma/kcms/screenlocker_kcm/contents/ui/main.qml and tried replacing that with my custom sddm theme with its main.qml file.
Alas! Didn't change the look of the lockscreen at all. Still uses the main Plasma theme look. Actually I experimented by removing everything from that folder and it still doesn't change the password dialogue screen at all. It still pop ups from the general Plasma theme.

Yes, I know you can provide a custom static background but it still uses the layout of the Plasma theme. It's kind of halfway there, it's the whole thing I'm trying to change.

Presumably you should be able to do your own qml-based screen locker (theme). Documentation seems a bit sparse.
I also found this article which provides quite a few details for customizing the screen locker (default theme): http://www.maketecheasier.com/customize ... ck-screen/
Of interest is that the location in KDE 4 for the screen locker UI is /usr/share/kde4/apps/ksmserver/screenlocker/org.kde.passworddialog/, but things changed quite a bit in KDE 5, so it may be in a different location (and likely in a different structure).

Hey,
in Plasma 5, the lockscreen QML file of the Breeze theme is located in /usr/share/plasma/look-and-feel/org.kde.breeze.desktop/contents/lockscreen/LockScreen.qml.
Overwriting or just editing this file would be a possible workaround.
I recommend to take a look at this file if you are already familiar with qml. In fact you just have to connect your UI to some signals and slots.

If you're happy enough to leave the layout as is and just change the background image, then the solution is very simple:

All you need to do is open the file

Code: Select all

~/.config/kscreenlockerrc

and edit it to refer to the background image you want.