callbacks.clj

(ns media-mogul.frontend.callbacks)

(defmulti renderer (fn [ state container graphics ] (:view state) ))
(defmethod renderer :default
 [ state container graphics ]
 (doto graphics
  (.drawString "Using default renderer", 30, 30)))

(defmulti updater (fn [ state container delta ] (:view state) ))
(defmethod updater :default
 [ state container delta ])

frontend.clj

(def state
  ref { :view :main-menu })

(def application-proxy
 (proxy [ BasicGame ] [ "Media Mogul" ]
  (init [ container ])
  (render [ container graphics ]
   (renderer @state container graphics))
  (update [ container delta ]
   (updater @state container delta))))

main-menu.clj

(ns media-mogul.frontend.main-menu
 [ :use [ media-mogul.frontend [ callbacks :only [ updater renderer ] ] ] ])

(defmethod updater :main-menu
 [ state container delta ]
 (.setTitle container "Main menu"))

(defmethod renderer :main-menu
 [ state container graphics ]
 (.drawString graphics "Hello, world!" 30 30))