title: Android: System Tools: Display System Level Alerts: How to use this Permission?
body: <p>There is an app on the Google "Play Store" called "Screen Filter", which is designed to cover the entire screen with some translucent black, to allow the screen to be dimmer than the minimum brightness.</p>
  
  <p>It does this using a permission called "Display System-Level Alerts".</p>
  
  <ol>
  <li><p>Where is the documentation that allows me to do this in my app?</p></li>
  <li><p>Can this "system-level alert" intercept touch events? This is so I can get my app to take over <a href="https://stackoverflow.com/questions/9590851/does-android-support-lock-down-to-a-fully-replaced-interface/9591107#comment12164786_9591107">an Android that is supposed to stay in our building</a>.</p></li>
  </ol>
  
  <p>I like this approach because it prevents the phone from being turned off before it is turned over (which would trigger an alarm), unless of course there is a hammer involved.</p>