The LibInput::Device provides a way to enable/disable the device.
This is used by the Connection to toggle all touchpad devices on/off
when the touchpad key is pressed. This is a hard coded key and not
mapped to a global shortcut (maybe it should?).
Detecting what is a touchpad is unfortunately not tivial. The code
uses the following approach:
- it's a pointer
- it's not also a keyboard or touch screen
- it's at least one of the following:
- supports multiple tap fingers
- supports disable while typing
- supports disable on external mouse
If the code finds a touchpad and changes it's state successfully,
it triggers the touchpadEnabledChanged on Plasma's osdService.