You could create a launcher and add it to your launcher bar by drag&dropping the .desktop-file there:
#!/usr/bin/env xdg-open
[Desktop Entry]
Version=1.0
Type=Application
Terminal=false
Icon[en_US]=nautilus
Name[en_US]=Connect to xy
Exec=shfs user@192.xx.xx.xx.xx:/dir/dir /home/username/mount/xxx
#OR: to mount and than open in nautilus (note the '/dir' where ':dir' used to be)
#Exec=nautilus sftp://user@192.xx.xx.xx.xx/dir/dir
Comment[en_US]=Connect to xy via ssh
Name=Connect to xy
Comment=Connect to xy via ssh
Icon=nautilus
Suggestion - even less work:
If you want even less work (=autoconnect) and a graphical user interface, you might want to check out Gigolo
. It has the capability of auto-mounting a bookmark, whenever the bookmarked filesystem is present. You might want to check that out.
sudo apt-get install gigolo # or use the install link above
Run gigolo. There is an option in the preferences that puts it into autostart and another to activate the tray icon. Check both. Then add your bookmark.
Here is a screenshot:

Shell way
Another solution would be to put the following line in your crontab (edit /etc/crontab with sudo privileges):
@reboot sshfs user@192.xx.xx.xx.xx:/dir/dir /home/username/mount/xxx
But since Ubuntu's password manager is not present when the command is run you need to use a password-less private/public key pair to authenticate with the ssh server in question (or a similar method of authentication). This would mount it on every reboot.
Yet another solution would be to edit your /etc/fstab (providing your Ubuntu-Version provides that option).