title: cannot find symbol class NotificationManagerCompat
body: <p>I am trying to build a notification method that would result in a notification appearing on the locked screen when a particular beacon is detected.  My understanding is that I need to include .setVisibility(0) in the following code:</p>
  
  <pre><code>public void showNotification(Beacon beacon) {
  
      Resources r = getResources();
      int random = (int)System.currentTimeMillis();
      Notification notification = new NotificationCompat.Builder(this)
              .setSmallIcon(android.R.drawable.ic_popup_reminder)
              .setContentTitle("Beacons Found")
              .setContentText(beacon.getID().toString())
              .setVisibility(0)  // allow notification to appear on locked screen
              .setAutoCancel(true)
              .build();
  
      NotificationManager notificationManager = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
      notificationManager.notify(random, notification);
  
  }
  </code></pre>
  
  <p>I have the above code, but when I run it it says "cannot find symbol variable SetVisibility".  I have done some research online and it seems I need to import this:</p>
  
  <pre><code> import android.support.v4.app.NotificationManagerCompat;
  </code></pre>
  
  <p>But if I include this import statement, it would say "cannot find symbol class NotificationManagerCompat"</p>
  
  <p>What should I do?  I have already installed Android Support Repository SDK and have the "android-support-v4.jar in the libs folder of the project</p>