title: How to animate marker on google maps ?
body: <p>What i'm trying to achieve supposed to be very simple, yet it's not working. 
  I have added a marker on my map, and i'm trying to animate it an heart beat. </p>
  
  <p>I have tried the following code, but without no luck, </p>
  
  <pre><code>   ObjectAnimator pulse = ObjectAnimator.ofPropertyValuesHolder(userLocation,
              PropertyValuesHolder.ofFloat("scaleX",2f),
              PropertyValuesHolder.ofFloat("scaleY",2f)
              );
      pulse.setDuration(310);
      pulse.setRepeatCount(ObjectAnimator.INFINITE);
      pulse.setRepeatMode(ObjectAnimator.REVERSE);
      pulse.start();
  </code></pre>
  
  <p>any suggestion would be grateful, 
  plus using an external library can be an option as well, I have just didn't find one. </p>