This has been bothering me very much. i have memory that Ubuntu 12.04 had this configuration? am i wrong? finally, is it possible for the login screen to have different wallpaper from the desktop? is this possible in Ubuntu 15.04? i would appreciate a stable understandable response. thanks :) -ben
I'm going to go ahead and post what worked for me. I found multiple threads trying to tell me how to change this, but this method is the only one that worked for me on Ubuntu 15.04. Some of the steps might not be entirely necessary, these are just the steps I ended up taking.
Get the picture you want to put as the login screen background. Place it in
/usr/share/backgrounds/and make sure the owner is
Root:Rootand the permissions match the other pictures in the folder (
-rw-r--r-- or 644).
/usr/share/glib-2.0/schemas/and open the file
Find the key name
backgroundand change the default to the path of your picture in "
/usr/share/backgrounds/. For the key names
draw-grid, change the default value to
Save your changes, then run the command
sudo glib-compile-schemas /usr/share/glib-2.0/schemas/
Restart the computer and your new login background should be there. Well, it was for me at least.
Hope this helps someone. No need to install anything, open
dconf-editor, deal with the LightDM user or anything terribly complicated.
Source: Changing the Wallpaper
Yes you can set different wallpapers for login screen and desktop, I found the working solution from here, which says:
LightDM does not configure the look of greeters; to do this configure the appropriate greeter.
Unity Greeter by default shows the currently selected users background. To set the default background and stop the switching edit
[com.canonical.unity-greeter] draw-user-backgrounds=false background='/foo/wallpaper.png'
sudo glib-compile-schemas /usr/share/glib-2.0/schemas/to apply these settings.
For LightDM GTK+ greeter edit
Then just logout or restart to see the change, hope this helps :)
I have looked all around for an answer, too, and it seems that 15.04 breaks from convention in lightdm configurations.
I'm new to this, so it's not an elegant solution but it answer's your primary question. I renamed the background that I wanted to display at the lightdm login to the default background (warty-final-ubuntu.png) while adding .bak to the original background file.
cd /usr/share/backgrounds/ sudo mv warty-final-ubuntu.png warty-final-ubuntu.png.bak sudo cp /path/to/my/background.png warty-final-ubuntu.png
Take it for what it's worth, but it works for me.