Android: How to turn screen on and off programmatically?

Question

Before marking this post as a \"duplicate\", I am writing this post because no other post holds the solution to the problem.

I am trying to turn off the device, then

Answer 1

     WakeLock screenLock =    ((PowerManager)getSystemService(POWER_SERVICE)).newWakeLock(
    PowerManager.SCREEN_BRIGHT_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP, "TAG");
    screenLock.acquire();

  //later
  screenLock.release();

//User Manifest file