want to show a image when enter a particular region of lat. long by zoom in and out android
<p>hi friends i am able to display Google map in my android device and by default i am able to perform zoom in and out,so  now i want to show a image when i enter,A REGION of between lat. long then a small pop msg appear at top of google map as "you enter buenos region"(Buenos is just place name whose coordinate area i take),so now how to show it in android,i have consult with iphone developer who develop same concept using the code below,but i am not understanding how to implement for zoomin and out for getting lat. long. of particular region..pls take  a look below...</p>

<pre><code>   if((centerCoordinate.latitude &lt; -34.538238) &amp;&amp; (centerCoordinate.latitude &gt; -34.672182))
   {
      if((centerCoordinate.longitude &lt; -58.347702) &amp;&amp; (centerCoordinate.longitude &gt; -58.528976))
  {
  img_City.hidden = NO;
 }
 else 
     {
  img_City.hidden  = YES;
     }

 }
</code></pre>
