NOTE: This command is only partially supported at this time. (It will set the lockScreen property, but that property currently has no effect). Theunlock screen command sets the lockScreen property to false, allowing for the screen to be updated. In addition, the with visualEffect option specifies a single visual transition that occurs as teh screen is updated. Visual effects can't be compounded using unlock screen, as they can be using the visual command. Visual effects compounded by the visual command are not executed until a go command is encourtered. The system flushes unexecuted visual effects and sets lockScreen to false at idle (in effect, at the end of all pending handlers).