title: How to make anything when my geolocation is changed?
body: <p>I want to make some action, i.e. show dialog with text 'im here' every time when my geolocation will be changed. </p>
  
  <p>I'm using MyLocationOverlay to draw a dot on my location on the Google Maps's mapview.</p>
  
  <p>How can I achieve that? </p>