jQuery Forum

I was having a similar trying to update the data theme to some custom-built themes based on certain events.

Started out setting the data-theme attribute but this only refreshed the first couple times and then stopped:
var myButton = document.getElementById('myButton');
myButton.setAttribute('data-theme', 'k');

When I examined the button with Firebug, the class of the button was being added to every time I changed themes, so that there was a long list of classes.  I think this was causing the issues.
class = "ui-btn ui-btn-corner-all ui-shadow ui-btn-up-a ui-btn-up-e ui-btn-up-j ui-btn-up-k"

So, I also set the class attribute each time and everything seemed to refresh fine:
myButton.setAttribute('class', 'ui-btn ui-btn-corner-all ui-shadow ui-btn-up-k');

Note: I found that you have to do both...set the data-theme and class.

That's exactly what I'm doing as well. 

I seem to have found a way to get jquery to refresh the class by specifically calling for pageshow event after I make adjustments to the HTML.  Not sure if this is the most efficient way to do it as it does seem a refresh option is needed but it works for me.

$('#PageName').trigger("pageshow");

Thanks gtracy!  This really solved my problem.  

There are probably other classes that have to stay, so preferably you only change the themed classnames.