title: Difference between Wakelock and FLAG_KEEP_SCREEN_ON?
body: <p>Keeping the screen awake can be accomplished by using a wakelock by</p>
  
  <pre><code>mWakeLock = mPowerManager.newWakeLock(PowerManager.SCREEN_BRIGHT_WAKE_LOCK, 
                  getClass().getName());
  </code></pre>
  
  <p>Or by adding the FLAG_KEEP_SCREEN_ON to the window,</p>
  
  <pre><code>getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
  </code></pre>
  
  <p>What is the technical difference between the two and in terms of performance and battery life which is recommended?</p>