code: function() {
          // clear the background
          me.game.world.addChild(new me.ColorLayer("background", "rgba(248, 194, 40, 1.0)"), 0);
  
          // add the UI elements
          var panel = new game.UI.Container(150, 100, 450, 325, "OPTIONS");
  
          // add a few checkbox
          panel.addChild(new game.UI.CheckBoxUI(
              125, 75,
              game.texture,
              "green_boxCheckmark",
              "grey_boxCheckmark",
              "Music ON", // default
              "Music OFF"
          ));
          panel.addChild(new game.UI.CheckBoxUI(
              125, 125,
              game.texture,
              "green_boxCheckmark",
              "grey_boxCheckmark",
              "Sound FX ON", // default
              "Sound FX OFF"
          ));
  
          // a few buttons
          panel.addChild(new game.UI.ButtonUI(
              125, 175,
              "blue",
              "Video Options"
          ));
          panel.addChild(new game.UI.ButtonUI(
              30, 250,
              "green",
              "Accept"
          ));
          panel.addChild(new game.UI.ButtonUI(
              230, 250,
              "yellow",
              "Cancel"
          ));
  
          // add the panel to word (root) container
          me.game.world.addChild(panel, 1);
  
          // display the current pointer coordinates on top of the pointer arrow
          this.font = new me.Text(0, 0 ,{
              font: "Arial",
              size: 10,
              fillStyle: "white",
              textAlign: "center",
              textBaseline: "top",
              text: "(xxx, xxx)"
          });
          me.game.world.addChild(this.font, Infinity);
  
          // display the current pointer coordinates on top of the pointer arrow
          var self = this;
          me.event.subscribe(me.event.POINTERMOVE, function(event) {
              var x = Math.round(event.gameScreenX);
              var y = Math.round(event.gameScreenY);
              self.font.pos.set(x, y - self.font.height, self.font.pos.z);
              self.font.setText( "( " + x + "," + y + " )");
          });
  
      }
docs: action to perform on state change