JQuery UI dialog does not pop up

I try to build an Announcement pop up function. Currently, i have a call back function to check whether someone modify the announcement.html.

So here is the code

<div id="popupDialog" class="cs_AnnoucementPop">
    <?=$this->data['Popup']?>
    test
</div>

<script type="text/javascript">
setInterval("_checkUS2PopUpUpdate()", 12000); //12 seconds (debugging - change back to 50)
</script> 

So, every 12 seconds, there will an Ajax call

function _checkUS2PopUpUpdate()
{
    var callback=new Object();
    callback.success=this.onExternalSuccess;
    callback.failure=this.onExternalFailure;
    YAHOO.util.Connect.asyncRequest('GET','/ci/ajaxCustom/ajaxUS2CheckPopupUpdate',callback);
};
function onExternalSuccess (o){
    if(o.responseText!==undefined)
    {
    var str=o.responseText;
    //document.getElementById('updateContent').innerHTML=str;
    if(str !== 'no update2') // Then pop up.
    {
        // This code is valid for jQuery-ui but it is not working. I think jQuery is being imported somewhere else and overwriting
        // jQuery-ui - I have set it back to the original popup for now - Matt Drewery
            $.noConflict();
        $.get('/euf/assets/announce开发者_开发百科ments/pop_up_announcement_us2.html', function(data) {
                    $('#popupDialog').html(data);
                    $('#popupDialog').dialog({modal: true});
            });

            /*L=screen.width-200;
        T=screen.height;
        popup=window.open(str,"",'alwaysRaised=yes,status=no,toolbar=no,location=no,menubar=no,directories=no,resizable=no,scrollbars=no,height=200,width=330,left="+L+",top="+T');
        for (i=0;i<200;i++)
        {
        T=T-1;
        popup.moveTo(L,T);
        }*/
        }
    }

}

When someone send an announcement, it calls to load the HTML file and try to pop up by using JQuery UI dialog

However, I got a break error. I do not know how to go further. Thanks.

$( [Break On This Error] $('#popupDialog').dialog({modal: true});

With JQuery you can not use the noConflict method and later use the $ sign. Check the docs for this on http://api.jquery.com/jQuery.noConflict/

Try this

$.noConflict();
jQuery.get('/euf/assets/announcements/pop_up_announcement_us2.html', function(data) {
 jQuery('#popupDialog').html(data);
 jQuery('#popupDialog').dialog({modal: true});
});