keyboard_events.dart

@override
  bool onKeyEvent(RawKeyEvent event, Set<LogicalKeyboardKey> keysPressed) {
    final isKeyUp = event is RawKeyUpEvent;
    //
    if (isKeyUp) {
      if (current == PlayerState.right || current == PlayerState.left || current == PlayerState.jump) {
        stop();
        current = PlayerState.regular;
      }
    }
    if (keysPressed.contains(LogicalKeyboardKey.arrowLeft)) {
      current = PlayerState.left;
      moveLeft();
    }

    if (keysPressed.contains(LogicalKeyboardKey.arrowRight)) {
      current = PlayerState.right;
      moveRight();
    }

    // During development, its useful to "cheat"
    if (keysPressed.contains(LogicalKeyboardKey.arrowUp)) {
      current = PlayerState.jump;
      moveUp();
    }

    if (keysPressed.contains(LogicalKeyboardKey.arrowDown)) {
      moveDown();
    }

    if (keysPressed.contains(LogicalKeyboardKey.space)) {
      current = PlayerState.hit;
      Future.delayed(const Duration(milliseconds: 99), () {
        if (current == PlayerState.hit) {
          current = PlayerState.regular;
        }
      });
    }

    if (keysPressed.contains(LogicalKeyboardKey.shiftLeft)) {
      current = PlayerState.shoot;
      final ice = Ice();
      (gameRef as MortalKombat).add(ice);
    }

    return true;
  }