anchor.diff:        scoreText.text = "Score: ${score+=10}";
       });
   
  -    game.physics.collison(ufos, player, (Ufo ufo, Ship player) {
  +    game.physics.collison(ufos, player, (Ufo ufo, Sprite player) {
         bulletTimer.cancel();
         killState();
       });
  
positive.code:     score = 0;
      scoreText = game.add.text("Score: $score", size: 20);
  
      player = new Ship.textureatlas(this, 'playerShip1_blue', 'spaceinvader')
          ..x = game.world.width ~/ 2
          ..y = game.world.height - 200
          ..speedX = 300;
  
      bullets = new Group<Sprite>();
      for (int i = 0; i < 5; i++) {
  
negative.code:           ..x = game.world.width - rightButton.width.toInt()
            ..y = game.world.height - 100;
  
        game.touch.onTouchBeginAndEnd(
            leftButton,
            () => player.go('left'),
            () => player.stop('left'));
  
        game.touch.onTouchBeginAndEnd(
            rightButton,
            () => player.go('right'),
            () => player.stop('right'));
  
      } else {
  
        game.keyboard.onDownAndUpKeyHandler(
            KeyCode.LEFT,
            () => player.go('left'),
            () => player.stop('left'));
  
        game.keyboard.onDownAndUpKeyHandler(
            KeyCode.RIGHT,
            () => player.go('right'),
            () => player.stop('right'));
  
      }
  
  
      //player.go('none', speedX: 0, speedY: 0);
    }
  
    update() {
  
      /*player.speedX = 0;
      if(game.keyboard.isDown(KeyCode.LEFT)){
        player.speedX = -300;
      }else if(game.keyboard.isDown(KeyCode.RIGHT)){
        player.speedX = 300;
      }*/
  
  
      if (!ufos.anyAlive()) {
        bulletTimer.cancel();
        killState();
  