cocos2d-x关于home键黑屏和游戏loading界面

有时候场景中的资源加载过多的话就会引起游戏进入的时候很卡，因为那是边加载边显示。还有在游戏中按下home键 再进入游戏的时候会有一段时间的黑屏，那是因为游戏要重新加载资源，这样用户体验非常不好。

我在tests例子里面发现一个很好的例子叫做TextureCacheTest，里面讲解了如何写loading。

首先在类头文件里面写上：

	//loading......callback
	void loadingCallBack(cocos2d::CCObject *obj);
	void addSprite();

	cocos2d::CCLabelTTF *m_pLabelLoading;
	cocos2d::CCLabelTTF *m_pLabelPercent;
	int m_nNumberOfSprites;//计数用 在构造函数中初始化成要加载的资源个数
	int m_nNumberOfLoadedSprites;//初始化为0

然后在cpp里面实现：这是我随便截取的代码

CCSize size = CCDirector::sharedDirector()->getWinSize();
//////////////////////////////////////////////////////////////////////////
	//loading界面
	m_pLabelLoading = CCLabelTTF::create("loading...", "Arial", 15);
	m_pLabelPercent = CCLabelTTF::create("%0", "Arial", 15);

	m_pLabelLoading->setPosition(CCPointMake(size.width / 2, size.height / 2 - 20));
	m_pLabelPercent->setPosition(CCPointMake(size.width / 2, size.height / 2 + 20));

	this->addChild(m_pLabelLoading,10);
	this->addChild(m_pLabelPercent,10);
//////////////////////////////////////////////////////////////////////////
	CCTextureCache::sharedTextureCache()->addImageAsync("gobacknormal.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("gobackselected.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/achievementnormal.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/achievementselected.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/Bighurdle1normal.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/Bighurdle2normal.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/Bighurdle3normal.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/Bighurdle1selected.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/Bighurdle2selected.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/Bighurdle3selected.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/Bighurdle1lock.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/Bighurdle2lock.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/Bighurdle3lock.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/Bighurdle2lockselected.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/Bighurdle3lockselected.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Bighurdle/main.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));
	CCTextureCache::sharedTextureCache()->addImageAsync("Smallhurdle/starfull.png", this, callfuncO_selector(BighurdleLayer::loadingCallBack));

然后在回调函数

void BighurdleLayer::loadingCallBack(cocos2d::CCObject *obj)
{
	++m_nNumberOfLoadedSprites;
	char tmp[10];
	sprintf(tmp,"%%%d", (int)(((float)m_nNumberOfLoadedSprites / m_nNumberOfSprites) * 100));
	m_pLabelPercent->setString(tmp);

	if (m_nNumberOfLoadedSprites == m_nNumberOfSprites)
	{
		this->removeChild(m_pLabelLoading, true);
		this->removeChild(m_pLabelPercent, true);
		addSprite();//这里是自己写得添加精灵的函数
	}
}

如果有更好的方法，请告知我，谢谢 共同进步

二.当按home键到桌面去，然后回到游戏弹出个进度条 然后游戏开始

我们只需要在AppDelegate.cpp里面添加layer就可以了 然后layer里面弄上定时器 一段时间后自动取消

// this function will be called when the app is active again
void AppDelegate::applicationWillEnterForeground()
{
	CCSize winSize = CCDirector::sharedDirector()->getWinSize();
	Loading *loading = new Loading();
	//CCSprite *sp = CCSprite::create("HelloWorld.png");
	//sp->setPosition(ccp(winSize.width/2, winSize.height/2));
	//loading->addChild(sp);
	CCDirector::sharedDirector()->getRunningScene()->addChild((CCNode *)loading);