Task: D-Bus - Battery Level

Navigate to labs/lab-12/tasks/dbus/support. Use D-Bus to find out the computer’s battery level. There is the org.freedesktop.UPower interface on the system bus that can provide this information. The method you need to call is org.freedesktop.DBus.Properties.Get from the /org/freedesktop/UPower/devices/DisplayDevice object.

This method needs 2 arguments: an interface name and a property name. Those should be org.freedesktop.UPower.Device and Percentage respectively.

Then input all of the above into a gdbus call, which, if everything is correct, should output the battery percentage level as a number between 0 and 100.

Note: if you are running on a desktop computer or inside a virtual machine, you will get the value 0.0, because those systems don’t have a battery.

If you’re having difficulties solving this exercise, go through this reading material.