Javascript widget for uservoice - auto-fill feedback form when loading page

Question

On an HTML page, how can I find out when a specific external javascript object is defined and ready to call methods on it?

Features of the problem:

I am using a uservoice web feedback application, including their javascript widget and their SSO (Single-SignOn).

Everything works perfectly. In the left part of the window is a noticeable tab "Feedback". And I can use the following anchor for sitelinks to open my backtip widget:

<a href="#" onclick="UserVoice.Popin.show(uservoiceOptions); return false;">feedback</a>

But ... I had problems with supporting an additional workflow - on one page (for example, on the feedback page). I want the uservoice feedback form to pop up automatically when the user navigates to the page without being clicked.

I tried putting the following at the bottom of the page:

<script type="text/javascript">
function _autoPopupUserVoice() {
  UserVoice.Popin.show(uservoiceOptions);
}
_loadSuper = window.onload;
window.onload = (typeof window.onload != 'function') ? _autoPopupUserVoice : function() { _loadSuper(); _autoPopupUserVoice(); };
</script>

But Firebug shows the error " UserVoice not defined". Therefore, I assume that the uservoice JavaScript code was not executed by the time it is called _autoPopupUserVoice().

I tried a few other things, but I was not able to get it to work. How to know when a javascript object is Uservoiceloaded and ready to call methods on it?

For reference, the Uservoice object is loaded through the following javascript at the end of the page:

<script type="text/javascript">
function _loadUserVoice() {
  var s = document.createElement('script');
  s.setAttribute('type', 'text/javascript');
  s.setAttribute('src', ("https:" == document.location.protocol ? "https://" : "http://") + "cdn.uservoice.com/javascripts/widgets/tab.js");
  document.getElementsByTagName('head')[0].appendChild(s);
}
_loadSuper = window.onload;
window.onload = (typeof window.onload != 'function') ? _loadUserVoice : function() { _loadSuper(); _loadUserVoice(); };

Answer 1

javascript, , Uservoice. 100 , Uservoice. , Popin :

<script type="text/javascript">

// Show the Uservoice feedback widget
function _autoPopupUserVoice() {
    UserVoice.Popin.show(uservoiceOptions);
}

// Wait for the uservoice JS object to load, fire _autoPopupUserVoice when it is finished.
if ((typeof window['UserVoice'] == 'undefined')) {

    var timer = setInterval(function () {
        ok = false;
        try { ok = (typeof window['UserVoice'] != 'undefined');} catch (e) {}

        if (ok) {
            clearInterval(timer);
            _autoPopupUserVoice();
        }
    }, 100);
}
</script>

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(8/Dec/09): - Uservoice:

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