I've spent a few hours looking for this. My test device is a nexus 6, though it has been tried on android 4.4 and 5.0+ as well.
Basically I want to catch a user's click of the onBackPress, but I want to do this outside of the activity. Say I've got an object that is initialized and while its running, It is to handle onBackPress, until the its killed.
I've looked into setting an onKeyListener to the contentView but that does not work at all (I figured as much, but its worth a shot).
Any idea how to do this (again, outside the scope of overriding in the activity)?