I know this is an old thread however I have to stick my oar in.

1. using the lock signal on dbus is silly because..what if your phone has autolock on a timeout? Potentially you could have to unlock>lock just to activate the thing!

2. Dbus scripts, while really cool is pretty heavy on cpu power, what with waking up to check every thing against it's rule set.


A far better way to do this is:

This sets the disable off then makes the file read only thats it. No daemons, no scripts nothing. Now with shortcutd you can set short press to task-switcher (which does nothing when the screen is off) and long press to skip/pause whatever.