I've being trying to add a theme from the Silverlight toolkit to a project. In the project there are a number of existing styles used in the layout.

The problem is when any control has an explict style applied to it does not receive any attributes of the style from the theme.

In WPF I would use something like BasedOn={x:Type TextBox}, but this is not supported in Silverlight.

I've considered going through the theme and setting a key for every style and then using BasedOn to create both an implicit style to use with the ImplictStyleManager, as well as another explicit style for use with the existing styled controls.

Have you got any better ideas?