title: Adding new markers on map using cluster manager doesn't reflect the changes until I zoom in and zoom out the map
body: <p>When I add new markers on the map programmatically using cluster manager it doesn't reflect the changes until I update the zoom in and zoom out.</p>
  
  <p>I have seen lots of questions on stack overflow  but that doesn't work for me,</p>
  
  <p>So please tell me how to update the map without clearing the map.</p>
  
  <p>Code:</p>
  
  <pre><code> for (int i = 0; i &lt; name.length; i++)
   { 
     Person_marker person_marker = new Person_marker(createRandLocation(latLng),
     name[i], getAddress(latLng), typedArray.getResourceId(i, -1), time[i], acuracy[i]);
     person_markerList.add(person_marker);
   } 
  clusterManager.clearItems(); clusterManager.addItems(person_markerList);
  </code></pre>