title: AdMob for Android: listener to click event
body: <p>I would like to detect when a user clicks on an AdMob banner.</p>
  
  <p>I realized that most banners nowadays open only after a confirmation click.</p>
  
  <p>AdMob provides <code>AdListener()</code> and its callback <code>onAdOpened()</code>, but such callback is not fired by the first click, it is only fired by the confirmation click which opens the ad.</p>
  
  <p>Is there a way to detect the first click on the AdMob banner?</p>