I've installed the util from PPA
sudo add-apt-repository ppa:atareao/atareao
sudo apt-get update
sudo apt-get install touchpad-indicator
In the software preferences I've selected "Disable touchpad on typing" and "Disable touchpad when mouse plugged"
Both don't work.
root@workbee:/home/alex# xinput
⎡ Virtual core pointer id=2 [master pointer (3)]
⎜ ↳ Virtual core XTEST pointer id=4 [slave pointer (2)]
⎜ ↳ SEM USB Keyboard id=9 [slave pointer (2)]
⎜ ↳ Synaptics TM3336-001 id=12 [slave pointer (2)]
⎜ ↳ SEMICCHIP Usb Mouse id=10 [slave pointer (2)]
⎣ Virtual core keyboard id=3 [master keyboard (2)]
↳ Virtual core XTEST keyboard id=5 [slave keyboard (3)]
↳ Video Bus id=6 [slave keyboard (3)]
↳ Power Button id=7 [slave keyboard (3)]
↳ SEM USB Keyboard id=8 [slave keyboard (3)]
↳ EasyCamera: EasyCamera id=11 [slave keyboard (3)]
↳ Ideapad extra buttons id=13 [slave keyboard (3)]
↳ AT Translated Set 2 keyboard id=14 [slave keyboard (3)]
Ubuntu 16.04 x64
Lenovo IdeaPad 320-15IKB
UPDATE
I've remembered an important detail.
Sometimes ago (a week or two) I installed the same (I think) touchpad indicator on some other system. Unfortunately, I don't remember how I installed it, and what system exactly was, but I remember that it had a very useful option in its settings, something like "Input Source" or "Input Method". It was a dropdown menu with 3 options. By switching between options I was able to make Touchpad Indicator able to manage touchpad status. I want to have that settings again.
uname -r
report for kernel version?4.13.0-26-generic