关于cocos2d-x进度条的实现和异步加载资源

上一篇呢，介绍的是擦美女，挺好玩的，这篇咱们说一下我们的进度条的加载，先上图

这种过渡，我们在游戏里其实是经常看到的，下面呢，我就解析一下进度条的实现

上代码：

首先，我们建一个工程，就HelloWorld吧，然后我们更改一下它的回调函数：

HelloWorld.h

  

public:
	LabelTTF* percentLabel;
	LoadingBar* pero;
	int m_numSp ;
	int m_loadedSp ;
public:
    // there's no 'id' in cpp, so we recommend returning the class instance pointer
    static cocos2d::Scene* createScene();

    // Here's a difference. Method 'init' in cocos2d-x returns bool, instead of returning 'id' in cocos2d-iphone
    virtual bool init();  
    // implement the "static create()" method manually
    CREATE_FUNC(HelloWorld);
	void plistImageAsyncCallback(Texture2D* texture);
	void loadingCallBack(Ref * sender);
	void loadSeccess();

  下面是.cpp

  这里我们用到了cocos studio的只是，如果不太懂，就先跟着做，或者可以联系我

  

 Size visibleSize = Director::getInstance()->getVisibleSize();
    Vec2 origin = Director::getInstance()->getVisibleOrigin();
	m_numSp = 3; //需要加载的资源总数
	m_loadedSp = 0;//当前已经加载资源个数
	//加载进度条文件
	Widget * uiLayer = GUIReader::getInstance()->widgetFromJsonFile("jindutiao/NewUi_1.json");//导入.json文件
	this->addChild(uiLayer);

	//创建显示Loading: 的label  ，创建一个label
	auto loadLabel = LabelTTF::create("Loading:","Arial",20);
	loadLabel->setPosition(Point(visibleSize.width/2-30,visibleSize.height/2+30));  
	this->addChild(loadLabel,1);  

	//创建显示百分比的label 
	  percentLabel = LabelTTF::create("0%","Arial",20); 
	percentLabel->setPosition(Point(visibleSize.width/2+35,visibleSize.height/2+30));  
	this->addChild(percentLabel,2);

	pero = (LoadingBar *) uiLayer->getChildByName("ProgressBar_1");
	pero->setPosition(Vec2(visibleSize.width/2,visibleSize.height/2));

		//音效预加载
	 SimpleAudioEngine::sharedEngine()-> preloadEffect("elplo.wav");
	
	 SimpleAudioEngine::sharedEngine()->preloadBackgroundMusic("acc.mp3");
	//资源的加载
	auto cache = Director::getInstance()->getTextureCache();//加载

          //加载.png
	cache->addImageAsync("HelloWorld.png",CC_CALLBACK_1(HelloWorld::loadingCallBack,this));  

	//cache->addImageAsync("dabaojian2.jpg",CC_CALLBACK_1(HelloWorld::loadingCallBack,this)); 

            //加载.plist文件
	cache->addImageAsync("dabaojian.png",CC_CALLBACK_1(HelloWorld::loadingCallBack,this));
	cache->addImageAsync("dabaojian.png",CC_CALLBACK_1(HelloWorld::plistImageAsyncCallback,this));

	cache->addImageAsync("Desktop.png",CC_CALLBACK_1(HelloWorld::loadingCallBack,this));


	
    return true;
}

//加载.plist文件函数
void HelloWorld::plistImageAsyncCallback(Texture2D* texture)
{
	SpriteFrameCache::getInstance()->addSpriteFramesWithFile("dabaojian.plist");
	//SpriteFrameCache::getInstance()->addSpriteFramesWithFile("Desktop.plist");
}

//主回调函数，实现进度过渡
void HelloWorld::loadingCallBack(Ref * sender) {

	++m_loadedSp;
	float newPercent = ((float)m_loadedSp / (float)m_numSp) * 100;//计算进度条当前的百分比  
	int n = (int)newPercent;
	std::string num = StringUtils::format("%d%%",n);
	percentLabel->setString(num);//更新percentLabel的值  
	
	pero->setPercent(newPercent);//更新进度条  
	log("end");
	if (newPercent == 100)
	{
		
		loadSeccess();
	}
}
//切换场景
void HelloWorld::loadSeccess() {

	
	auto delaTime = DelayTime::create(3);
	
	CallFunc * callFunc = CallFunc::create([=](){
		auto scene = Hours::createScene();
		Director::getInstance()->replaceScene(scene);});

	this->runAction(Sequence::create(delaTime,callFunc,NULL));

	
}

这里呢，下一个场景的源码我就不往上面粘了，你可以自己建一个场景，创建你自己的场景过渡

好了，这篇博客呢，我们就到这里了，欢迎留言和指正错误，qq:3031260489