title: google-map-api3 how to remove an overlay using prototype
body: <p>I used the following two functions to project my overalays on a map:</p>
  
  <pre class="lang-js prettyprint-override"><code>  myOverlay.prototype.onAdd = function () { }
    myOverlay.prototype.draw = function () { }
  </code></pre>
  
  <p>However, I could not fine a way to remove the overlays. The following function is supposed to do the job, but I could not make it work. </p>
  
  <pre class="lang-js prettyprint-override"><code>  myOverlay.prototype.onRemove = function () {
        this.div_.parentNode.removeChild(this.div_);
        this.div_ = null;
    };
  </code></pre>
  
  <p>Could some experts help me out? 
  Thanks.</p>