How to change the theme dynamically after executing npm run build-themes

The template overrides any theme changing I do dynamically at runtime... 
ex) 
> DxThemes.current('material.blue.dark');

currently this doesn't work but in a different application that I havent executed "npm run build-themes" on this works.  

Is there a way to undo the template/ allow it to be overriden by a piece of code like above