title: "requestAnimationFrame" method is not working
body: <p>"requestAnimationFrame" method is not working in the following example. Console doesn't show any error messsage. Then what is the error in this code?
  html:</p>
  
  <pre><code>   &lt;body&gt;
        &lt;div id="container"&gt;
           &lt;canvas id="canvas" width="1024" height="1024"&gt;&lt;/canvas&gt;
        &lt;/div&gt; 
        &lt;script type="text/javascript" src = "Jquery/easy.js"&gt;&lt;/script&gt;
     &lt;/body&gt;
  </code></pre>
  
  <p>javascript:</p>
  
  <pre><code> var canvas = document.getElementById('canvas');
   var ctx = canvas.getContext('2d');
   var chop1 = new Image();
   chop1.src = "img/chopper.png";
   var chopperX = 0;
   var chopperY = 0;
   var ascent = 20;
  
   function fly()
   {
      chopperY += ascent;
      ctx.drawImage(chop1, chopperX, chopperY, 30, 80);
      requestAnimationFrame(fly);
  
   }
  
   window.onload = function() {
      init()
   };
  
   function init()
   {
      chop1.src = "img/chopper.png";
      ctx.drawImage(chop1, 0, 0, 30, 80);
      fly()
   }
   ;
  </code></pre>