I downloaded a couple greeters for LightDM, but I have not figured out how to enable them. Is there a way to switch greeter, either by graphical or command-line method?. I do not intend to change display manager, nor the background, but to change the layout and appearance of the login screen through a different "theme" (greeter is the name for LightDm themes). Thanks for your time.
Just edit the 'greeter-session' option in '/etc/lightdm/lightdm.conf' to the desired greeter.
If you for example want to use the 'lightdm-gtk-greeter'.
Open up '/etc/lightdm/lightdm.conf' with any editor as root. For example
Then all you have to do is to restart lightdm.
Change the LightDM Greeter
KDM, another desktop manager, has themes that may be changed using a configuration front end. LightDM has greeters that may be changed, but there is no front end.
LighDM configuration is governed by the lightdm.conf file, however it's not suppose to be directly edited, instead use the backend lightdm-set-defaults.
Before you change LighDM configuration, make a backup up the file:
There are several LightDM greeters, such as lightdm-unity-greeter, lightdm-gtk-greeter, lightdm-webkit-greeter, and lightdm-kde-greeter.
For this example I will use lightdm-kde-greeter.
If you are doing this from a root console, type all commands without sudo. For the following commands, if you are using a GUI (graphical user interface), use the key sequence ALT-F2 or the Super key (usually the Windows key) and type term to open a terminal of your choice. If KDE default terminal, just type konsole.
Follow these steps carefully.
I gleaned most of this information from the LightDM Ubuntu Wiki. Except for adding the PPA, the information is not release version specific and LightDM is beyond the testing stage. Read more at http://wiki.ubuntu.com/LightDM
If something goes horribly wrong.
You can change the LightDM greeter by doing the following in the Terminal:
For more information about LightDM, go to https://wiki.ubuntu.com/LightDM
try to use this little software to change easily lightdm theme (ppa made by Claudio Novais):
sudo apt-add-repository ppa:claudiocn/slm && sudo apt-get update
sudo apt-get install simple-lightdm-manager
Hope you enjoy it.
Install Ubuntu Tweak. Open it and select the "Tweaks" tab. Under "Startup" select "Login Settings". At the very top right hand corner is a search bar, just to it's left is the unlock. Unlock and you can change the gtk and icon theme on start up. Plus the logo and background. Hope that helps.
Are you trying to change from LightDM to some other DM, say gdm?
Then try dpkg-reconfigure gdm.
But I found LightDM is much faster than gdm. So don't know why would one like to change.