状态层是比较复杂的了，状态层需要与游戏层通信，因此也需要为游戏层先设计一个代理类，以便状态层遵守游戏层的代理，这样游戏层就可以在游戏开始、得分、结束时，告诉状态层做出相应的状态表现了。

游戏层的代理类：

/** * The delegate between status layer and game layer */class GameStatusDelegate {
     public:  /**   * When the game start, this method will be called   */  virtual void onGameStart() = 0;  /**   * During paying, after the score changed, this method will be called   *   * @param score The latest score   */  virtual void onGamePlaying(int score) = 0;  /**   * When game is over, this method will be called   *   * @param currentScore Current game score   * @param historyBestScore The best score in the history of the player   */  virtual void onGameEnd(int currentScore, int historyBestScore) = 0;};

只有三个方法，分别对应游戏开始、玩家得分、游戏结束。

那么状态层需要遵守代理：

/** *The status layer,showing the status information * in the game. */class StatusLayer : public cocos2d::Layer, public GameStatusDelegate

遵守代理后，必须声明代理中的方法：

/**   * Override from GameStatusDelegate   *   * @see GameStatusDelegate declaration.   */  void onGameStart(void);  void onGamePlaying(int score);  void onGameEnd(int currentScore, int historyBestScore);

如果不声明，会编译不通过的，这是必须实现的。

这个层中，有四种精灵需要控制：

cocos2d::Sprite *_getReadySprite;  cocos2d::Sprite *_tutorialSprite;  cocos2d::Node *_scoreNode;  cocos2d::Sprite *_blinkSprite;

分别对应GetReady、指导图、得分、闪屏图

在初始化时，先邓加载0~9数字精灵：

bool StatusLayer::init() {  if (!Layer::init()) {    return false;  }  // preload number sprite frames to memory  ScoreNumber::getInstance()->loadNumber(kScoreNumberFont.c_str(), "font_0%02d", 48);  ScoreNumber::getInstance()->loadNumber(kScoreNumberScore.c_str(), "number_score_%02d", 0);  // At the first time, the game is ready to play  this->showGameStatus(kGameStateReady);  return true;}

关于数字特效类ScoreNumber，后面再单独说明。

这个类中最重要的显示状态方法：

void StatusLayer::showGameStatus(GameState status, int currentScore, int historyBestScore) {  auto size = Director::getInstance()->getVisibleSize();  auto origin = Director::getInstance()->getVisibleOrigin();  switch (status) {    case kGameStateReady: {      const char *scoreName = kScoreNumberFont.c_str();      _scoreNode = ScoreNumber::getInstance()->convert(scoreName, currentScore);      _scoreNode->setPosition(origin.x + size.width / 2, origin.y + size.height * 5 / 6);      this->addChild(_scoreNode);      _getReadySprite = Sprite::createWithSpriteFrame(AtlasLoader::getInstance()->getSpriteFrame("text_ready"));      _getReadySprite->setPosition(origin.x + size.width / 2, origin.y + size.height * 2 / 3);      this->addChild(_getReadySprite);      _tutorialSprite = Sprite::createWithSpriteFrame(AtlasLoader::getInstance()->getSpriteFrame("tutorial"));      _tutorialSprite->setPosition(origin.x + size.width / 2, origin.y + size.height * 1 / 2);      this->addChild(_tutorialSprite);    }      break;    case kGameStateStarted: {      _getReadySprite->runAction(FadeOut::create(0.4f));      _tutorialSprite->runAction(FadeOut::create(0.4f));    }      break;    case kGameStateOver: {      _currentScore = currentScore;      _bestScore = historyBestScore;      if (_currentScore > _bestScore) {        _bestScore = _currentScore;        _isNewRecord = true;      } else {        _isNewRecord = false;      }      this->removeChild(_scoreNode);      // Game over      auto overSprite = Sprite::createWithSpriteFrame(AtlasLoader::getInstance()->getSpriteFrame("text_game_over"));      auto size = Director::getInstance()->getVisibleSize();      auto origin = Director::getInstance()->getVisibleOrigin();      overSprite->setPosition(origin.x + size.width / 2, origin.y + size.height * 2 / 3);      this->addChild(overSprite);      // Add animation      auto fadein = FadeIn::create(0.5f);      auto actionDone = CallFunc::create(std::bind(&StatusLayer::showScorePanel, this));      auto sequence = Sequence::createWithTwoActions(fadein, actionDone);      overSprite->stopAllActions();      overSprite->runAction(sequence);    }      break;    default:      break;  }}

如果状态为ready，即准备状态，

准备状态图：

状态为kGameStateStarted，表示开始游戏时，

_getReadySprite->runAction(FadeOut::create(0.4f)); _tutorialSprite->runAction(FadeOut::create(0.4f)); 只是添加淡出效果

状态为游戏结束时，显示游戏结束：

当游戏结束的时候，显示Game Over 精灵，然后添加淡入淡出的动画，来显示得分结果显示面板和重玩、机会按钮，

不过这里并没有实现机会使用按钮，因此此功能就留给喜欢研究扩展的朋友吧。

刷新得分面板用户得分函数，从0到玩家得分，有一个动画的过程，

void StatusLayer::refreshScoreUpdate(float delta) {  const int kCurrentSpriteTag = 100;  if (this->getChildByTag(kCurrentSpriteTag)) {    this->removeChildByTag(kCurrentSpriteTag);  }  const char *score = kScoreNumberScore.c_str();  _scoreNode = ScoreNumber::getInstance()->convert(score, _tmpScore, kGravityDirectionRight);  _scoreNode->setAnchorPoint(Vec2(1, 0));  auto size = Director::getInstance()->getVisibleSize();  auto origin = Director::getInstance()->getVisibleOrigin();  _scoreNode->setPosition(origin.x + size.width * 3 / 4 + 4, origin.y + (size.height - _scoreNode->getContentSize().height) / 2 + 7);  this->addChild(_scoreNode);  ++_tmpScore;  if (_tmpScore > _currentScore) {    unschedule(schedule_selector(StatusLayer::refreshScoreUpdate));  }}

这是通过定时器来回调的，当刷新完成时，需要取消掉定时器。

点击重玩按钮时，进入到此函数：

void StatusLayer::menuRestartCallback(cocos2d::Ref *pSender) {  CocosDenshion::SimpleAudioEngine::getInstance()->playEffect("sfx_swooshing.ogg");  // We can't add TransitionScene object, otherwise it can't receive any touch event.  // I don't know why.  // We should remove all children and clean up resources, otherwise it will crash at  // some time in the future. In fact, I don't know why, when Director replace a new  // scene, does it remove and clean up?  auto scene = Director::getInstance()->getRunningScene();  scene->removeAllChildrenWithCleanup(true);  Director::getInstance()->replaceScene(GameScene::createScene());}

如果不加上这两行代码先释放资源，时不时就会崩溃，不知道是不是因为是自动释放的，但是事件循环并没有到，因此一直没有得到释放而导致的。

auto scene = Director::getInstance()->getRunningScene();  scene->removeAllChildrenWithCleanup(true);

这两行代码只是先把当前场景的所有资源先释放掉。

下一步，看一看我们设计的数字特效类