Can someone please explain to me how can I have a download link appear when a user presses the share button on a feed dialog box? I'm using the following code: (with my own information of course)
Post to Feed
<script> 
  FB.init({appId: "YOUR_APP_ID", status: true, cookie: true});
  function postToFeed() {
    // calling the API ...
    var obj = {
      method: 'feed',
      link: 'https://developers.facebook.com/docs/reference/dialogs/',
      picture: 'http://fbrell.com/f8.jpg',
      name: 'Facebook Dialogs',
      caption: 'Reference Documentation',
      description: 'Using Dialogs to interact with users.'
    };
    function callback(response) {
      document.getElementById('msg').innerHTML = "Post ID: " + response['post_id'];
    }
    FB.ui(obj, callback);
  }
</script>
I have no clue on how to do is: what code do I need so that when a user clicks "share" a download box appears? But if they click cancel a message pops up telling them they need to share first? I have posted a similar question before and I got an answer saying I need to use some sort of JavaScript but the problem is I don't know how or what to write? Can someone please show and explain the sort of JavaScript I need to me because I don't know how to use JavaScript one bit.
Thanks in advance for any answers/help!!
 
    