A cover for an electronic device comprises: at least one sensor, wherein the at least one sensor detects the cover being partially opened; and a signal transmitter, wherein the signal transmitter: transmits, to a video controller in the electronic device, an opening signal in response to the cover being partially opened, wherein the opening signal is in response to the cover being partially opened, and wherein the opening signal identifies and enables a first portion of a display on the electronic device; and transmits, to the video controller in the electronic device, a disabling signal to disable a second portion of the display that is not identified by the opening signal.