Unity-2D comes default with Ubuntu 11.10 Oneiric, but previous 2d-desktp setting tool for Ubuntu 11.04 Natty to change unity-2d launcher preferences won’t working any more at here.
In Ubuntu 11.10 unity-2d desktop we can use dconf-tool instead.
To install dconf-editor:
sudo apt-get install dconf-tools
After installation, check unity-2D options with this command:
dconf list /com/canonical/unity-2d/launcher/
you will see something like this:
1.) let launcher always visible:
dconf write /com/canonical/unity-2d/launcher/use-strut true
2.) let launcher auto-hide when a window is placed on top of it and if the user is not interacting with it:
dconf write /com/canonical/unity-2d/launcher/use-strut 0