sudo gedit xx warning

When I sue command "sudo gedit xx", it appeas several warning:

gedit:2714): IBUS-WARNING **: The owner of /home/ecomu/.config/ibus/bus is not root!

(gedit:2714): Gtk-WARNING **: Calling Inhibit failed: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.gnome.SessionManager was not provided by any .service files

Actually, the correct command should like this:

gksudo gedit xx

 

PS: difference between commands "sudo" and "su"...