A couple of weeks ago, I requested to build a code sample for Microsoft. It was supposed to make it possible to restyle a Silverlight application based on a SharePoint 2010 theme. In SharePoint 2010, theming is based on OpenXML, and saved as files with an extension of “thmx”.
But I guess the first question would be WHY you would use a huge thmx file just to restyle a Silverlight application… Well, imagine that you are building Silverlight applications that are to be used inside a SharePoint application. Imagine how nice it would be if the Silverlight applications would change appearance if you changed the theme of the SharePoint site. That way, changing the theme would not be a problem, and would not cause a whole lot of rework.
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