Ubuntu Unity already has a dynamic desktop wallpaper that changes throughout the day, which are selected from the
/usr/share/backgrounds folder, but after a while a I got bored to see always the same images so I wanted to use my collection of images from the APOD, Astronomy Picture of the Day, website.
I thought that I could simply set a folder in System Settings -> Appearance but actually the only folder that you can select is the whole
~/Pictures folder, while I wanted to use only the
~/Pictures/Wallpapers. To solve my problem I could edit the
/usr/share/backgrounds/contest/precise.xml file, but this means that I have to update that file every time I download a new picture from APOD, so I had to find my own solution.
The idea is quite simple:
- select a random file from
- change the desktop background setting from the command line
- use a cron job to schedule the wallpaper change every 15 minutes
Select a Random File
This can be solved easily with a couple of lines in Python like this:
import os,random return random.choice(os.listdir('/home/your-name/Pictures/Wallpapers'))
You can copy in your
/home/your-name/bin directory a more usable version of this script from my Github repository random-file,
Change the Desktop Background from the Command Line
To change the desktop background from the command line you can use
$ gsettings set org.gnome.desktop.background picture-uri "file:///path/to/wallpaper.jpg"
Be aware that
gsettings is a new command introduced in GNOME3 and Unity, if you use the old GNOME2 you have to use
$ gconftool-2 --type=string --set /desktop/gnome/background/picture_filename /path/to/wallpaper.jpg
To find out what version you have, run:
$ gnome-session --version
You can put this command in a bash script to change your background but actually is not going to work when it is called from cron jobs, because the DBUS_SESSION_BUS_ADDRESS environment variable need to be set first.
Again, You can copy change-wallpaper from my Github repository in your
As I am using Ubuntu 12.04, my script calls
gsettings, but you're free to fork my dd-scripts and send me a pull request if you write a version for Gnome2.
Set a Cron Job
Now it's only a question of telling your system to change automatically the background every 15 minutes by editing your user's crontab table:
$ crontab -e
Then add these lines:
# Edit this file to introduce tasks to be run by cron. # # m h dom mon dow command */15 * * * * /home/your-name/bin/change-wallpaper
Great! Enjoy your new desktop wallpapers!