title: Accessing an iFrame's dom from a Firefox Extension
body: <p>I've spent a long time trying different things to get this to work but nothing does and documentation is not helping much.</p>
  
  <p>I'm trying to populate a form inside an iframe that I dynamically inject into a page. To inject that iframe I do:</p>
  
  <pre><code>myObject.iframe = document.createElement("iframe");
  myObject.iframe.setAttribute("src", data.url);
  myObject.iframe.setAttribute("id","extension-iframe");
  myObject.window.document.getElementById('publisher').appendChild(myObject.iframe);
  myObject.iframe.addEventListener("load", function(){
      myObject.populate(data);
  }, false);
  </code></pre>
  
  <p>which works fine and DOES trigger the populate() method. My problem is getting the document or window objects for that iframe. I've tried all of the following:</p>
  
  <pre><code>myObject.iframe.window
  myObject.iframe.document
  myObject.iframe.content
  </code></pre>
  
  <p>but these are all undefined.</p>
  
  <p>I also tried passing the event object to that iframe's load event listener and then doing:</p>
  
  <pre><code>event.originalTarget
  </code></pre>
  
  <p>But that didn't work either.</p>
  
  <p>I am reading the following documentation:</p>
  
  <ul>
  <li><a href="https://developer.mozilla.org/En/Working_with_windows_in_chrome_code" rel="nofollow noreferrer">https://developer.mozilla.org/En/Working_with_windows_in_chrome_code</a></li>
  <li><a href="https://developer.mozilla.org/en/Code_snippets/Interaction_between_privileged_and_non-privileged_pages" rel="nofollow noreferrer">https://developer.mozilla.org/en/Code_snippets/Interaction_between_privileged_and_non-privileged_pages</a></li>
  </ul>
  
  <p>But either I'm not understanding it or it's just not properly explained.</p>
  
  <p>Can anyone shed some light?</p>
  
  <p>Thanks!</p>