Glade - a User Interface Designer for GTK+ and GNOME
Glade is a RAD tool to enable quick & easy development of user interfaces for the GTK+ toolkit and the GNOME desktop environment, released under the GNU GPL License.
The user interfaces designed in Glade are saved as XML, and by using the libglade library these can be loaded by applications dynamically as needed.
By using libglade, Glade XML files can be used in numerous programming languages including C, C++, Java, Perl, Python, C#, Pike, Ruby, Haskell, Objective Caml and Scheme. Adding support for other languages is easy too.