installing a deck wiring

[hotrodharley]

install a deck in my 84 Chevy truck that has a 3"led screen in it with back up camera;;ion deck wiring it says to run the white wire to parking brake switch;;at this time the parking brake assy has been removed from truck;;haven't put one back in yet;;so do I just ground the white wire from deck or do I run it to a keyed + feed or do I just leave it not hooked up until I install park brake assy? I'm assuming the white wire is to keep driver from watching dvd while driving so if park brake is on is only time dvd will work;;guess what I'm asking is if you have park brake set then is there 12 volts leaving switch or is it a ground leaving the switch when set?