KDE and XFCE4 has a program to adjust the screen brightness automatically in battery mode to a preset value. How can i set the same with Unity ( or Gnome3 )?
Next you need to set up the reaction.Go to Reaction>Applications>Start Application(Advanced Mode)
Now choose the executable as dim(file that we created earlier)
You may also want to increase the brightness when power is plugged again.For that follow the same steps except write
To make it work, you need to enable cuttlefish to start automatically. Go to edit/preferences (within cuttlefish) and enable start up .
I find the solution:
If you have latop-mode installed
$ cat /sys/class/backlight/acpi_video0/brightness
$ cat /sys/class/backlight/acpi_video0/max_brightness
$ sudo gedit /etc/laptop-mode/conf.d/lcd-brightness.conf
BATT_BRIGHTNESS_COMMAND="echo [min value]"
LM_AC_BRIGHTNESS_COMMAND="echo [max value]"
NOLM_AC_BRIGHTNESS_COMMAND="echo [normal value]"