Themes in GXT, as with other UI platforms, provide a robust way to control the look and feel of the components and widgets available to an application. Besides the collection that ships with the standard GXT distribution, quite a number of GXT themes can be found online, making it possible to change from the bluish look of GXT applications to something different in color and even structure.
A GXT theme defines the set of images and CSS used for its styling of components, and can then be used together with the GXT theme-manager component so that the rest of the API can be dressed in the attire of the said theme.
This chapter will discuss how to use the standard bundled themes and third-party themes as well, before briefly touching on how to begin building custom themes for GXT applications.