I'm trying to set up some Backgrounds and wrote a custom xml for that (later on I want to make a custom slideshow of these). The images should span over my dual monitor.
$ cat /home/user/.local/share/gnome-background-properties/wallpapers.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE wallpapers SYSTEM "gnome-wp-list.dtd">
<wallpapers>
<wallpaper>
<name>Test1</name>
<filename>/home/user/Bilder/test1.jpg</filename>
<options>span</options>
<pcolor>#000000</pcolor>
<scolor>#000000</scolor>
<shade_type>solid</shade_type>
</wallpaper>
</wallpapers>
With options set to 'span' Control-Center does only show a black thumbnail. Starting Control-Center from terminal brings up an error:
$ gnome-control-center background
(gnome-control-center:7019): background-cc-panel-WARNING **: Unhandled value 'span' for enum 'GDesktopBackgroundStyle'
If I set options to 'zoom' everything works fine.
The correct value is
spanned
(notspan
), so it should work if you change it to that.I tested this on my Ubuntu 12.10 system with GNOME 3. It doesn't look very consistent though...