public void setGuiScreen(GuiScreen newScreen) {
	if (currentScreen != null) {
	    canvas.removeMouseListener(currentScreen);
	    canvas.removeMouseMotionListener(currentScreen);
	    frame.removeKeyListener(currentScreen);
	} else {
	    canvas.removeMouseListener(canvas.mapRenderer);
	    canvas.removeMouseMotionListener(canvas.mapRenderer);
	    canvas.removeMouseWheelListener(canvas.mapRenderer);
	    frame.removeKeyListener(canvas.mapRenderer);
	    canvas.mapRenderer = null;
	}
	currentScreen = newScreen;
	if (currentScreen != null) {
	    canvas.addMouseListener(currentScreen);
	    canvas.addMouseMotionListener(currentScreen);
	    frame.addKeyListener(currentScreen);
	}
    }