Index: makefile
===================================================================
--- makefile	(revision 699e83a728c7db8f10c4637546020207c0b0d4c0)
+++ makefile	(revision c205c3a8a3acc0125b6b0cea26e2879f383b1889)
@@ -60,5 +60,5 @@
 
 GUI_SRC_FILES = gui/screen.cpp gui/main-screen.cpp gui/game-screen.cpp gui/ui-element.cpp gui/button.cpp gui/panel.cpp
-GUI_HEADER_FILES = gui/screen.hpp gui/main-screen.hpp gui/game-screen.hpp gui/ui-element.hpp gui/button.hpp gui/panel.hpp
+GUI_HEADER_FILES = gui/screen.hpp gui/main-screen.hpp gui/game-screen.hpp gui/ui-element.hpp gui/button.hpp gui/panel.hpp gui/ui-value.hpp
 
 SRC_FILES = main-vulkan.cpp vulkan-game.cpp crash-logger.cpp logger.cpp vulkan-utils.cpp utils.cpp game-gui-sdl.cpp $(GUI_SRC_FILES)