'Tix maintains a list of directories under which
the  tix_getimage  and tix_getbitmap commands will
search for image files. The standard bitmap  directory
is $TIX_LIBRARY/bitmaps. The addbitmapdir command
adds directory into this list. By  using  this
command, the  image  files  of an applications can
also be located using the tix_getimage or tix_getbitmap
command.'

def tix_addbitmapdir(self, directory):

    return self.tk.call('tix', 'addbitmapdir', directory)
