Automatically resize jQuery UI dialog to the width of the content loaded by ajax

I've just wrote a tiny sample app using JQuery 1.4.1 and UI 1.8rc1. All I did was specify the constructor as:

var theDialog = $(".mydialog").dialog({
        autoOpen: false,
        resizable: false,
        modal: true,
        width:'auto'
});

I know you said that this makes it take up 100% width of the browser window but it works sweet here, tested in FF3.6, Chrome and IE8.

I'm not making AJAX calls, just manually changing the HTML of the dialog but don't think that will cause any probs. Could some other css setting be knocking this out?

The only problem with this is that it makes the width off-centre but I found this support ticket where they supply a workaround of placing the dialog('open') statement in a setTimeout to fix the problem.

Here is the contents of my head tag:

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.1/jquery.min.js"></script>
<script type="text/javascript" src="jquery-ui.min.js"></script>
<link href="jquery-ui.css" rel="stylesheet" type="text/css" />
<script type="text/javascript">
    $(function(){
        var theDialog = $(".mydialog").dialog({
            autoOpen: false,
            resizable: false,
            modal: true,
            width: 'auto'
        });

        $('#one').click(function(){
            theDialog.html('some random text').dialog('open');
        });

        $('#two').click(function(){
            theDialog.html('<ul><li>Apple</li><li>Orange</li><li>Banana</li><li>Strawberry</li><li>long text string to see if width changes</li></ul>').dialog('open');
        });

        $('#three').click(function(){
            //this is only call where off-centre is noticeable so use setTimeout
            theDialog.html('<img src="./random.gif" width="500px" height="500px" />');
            setTimeout(function(){ theDialog.dialog('open') }, 100);;
        });
     });
</script>

I downloaded the js and css for Jquery UI from http://jquery-ui.googlecode.com/files/jquery-ui-1.8rc1.zip. and the body:

<div class='mydialog'></div>
<a href='#' id='one'>test1</a>
<a href='#' id='two'>test2</a>
<a href='#' id='three'>test3</a>

Had the same problem and thanks to you mentioning that the real problem was related to CSS I found the issue:

Having position:relative instead of position:absolute in your .ui-dialog CSS rule makes the dialog and width:'auto' behave strangely.

.ui-dialog { position: absolute;}

Here's how I did it:

Responsive jQuery UI Dialog ( and a fix for maxWidth bug )

Fixing the maxWidth & width: auto bug.