cocos2d-x3.2中使用的C++11特性总结

1.auto关键字

2.std::thread

异步加载纹理可以使用 Director::getInstance()->getTextureCache()->addImageAsync

异步加载声音和处理网络请求可以使用std::thread

#include <thread>

void callfn(){

std::cout << "Hello thread! " << std::endl;

}

int main(){

std::thread* t1 = new std::thread(callfn);

t1->join();

deletet1;

t1 = nullptr;

return 0;

}

class AppDelegate : private cocos2d::Application

{

private:

std::thread *_loadingAudioThread;

void loadingAudio();

public:

};

AppDelegate::AppDelegate()

{

_loadingAudioThread = new std::thread(&AppDelegate::loadingAudio,this);

}

AppDelegate::~AppDelegate()

{

_loadingAudioThread->join();

CC_SAFE_DELETE(_loadingAudioThread);

}

void AppDelegate::loadingAudio()

{

//初始化 音乐

SimpleAudioEngine::getInstance()->preloadBackgroundMusic("sound/Jazz.mp3");

SimpleAudioEngine::getInstance()->preloadBackgroundMusic("sound/Synth.mp3");

//初始化 音效

SimpleAudioEngine::getInstance()->preloadEffect("sound/Blip.wav");

}

3.nullptr

4.Range for

5.Lambda函数和算法，一般在事件监听中使用可以使代码优化

= [](){};[]捕获变量列表

void
HelloWorld::onEnter()

{

Layer::onEnter();

log("HelloWorld onEnter");

// 创建一个事件监听器 OneByOne 为单点触摸

auto listener = EventListenerTouchOneByOne::create();

// 设置是否吞没事件，在 onTouchBegan 方法返回 true 时吞没

listener->setSwallowTouches(true);

// 使用 lambda 实现 onTouchBegan 事件回调函数

listener->onTouchBegan = [](Touch* touch, Event* event){

// 获取事件所绑定的 target

auto target = static_cast<Sprite*>(event->getCurrentTarget());

// 获取当前点击点所在相对按钮的位置坐标

Vec2 locationInNode = target->convertToNodeSpace(touch->getLocation());

Size s = target->getContentSize();

Rect rect = Rect(0, 0, s.width, s.height);

// 点击范围判断检测

if (rect.containsPoint(locationInNode))

{

log("sprite x = %f, y = %f ", locationInNode.x, locationInNode.y);

log("sprite tag = %d", target->getTag());

target->runAction(ScaleBy::create(0.06f, 1.06f));

return true;

}

return false;

};

// 触摸移动时触发

listener->onTouchMoved = [](Touch* touch, Event* event){

auto target = static_cast<Sprite*>(event->getCurrentTarget());

// 移动当前按钮精灵的坐标位置

target->setPosition(target->getPosition() + touch->getDelta());

};

// 点击事件结束处理

listener->onTouchEnded = [](Touch* touch, Event* event){

auto target = static_cast<Sprite*>(event->getCurrentTarget());

log("sprite onTouchesEnded.. ");

Vec2 locationInNode = target->convertToNodeSpace(touch->getLocation());

Size s = target->getContentSize();

Rect rect = Rect(0, 0, s.width, s.height);

// 点击范围判断检测

if (rect.containsPoint(locationInNode))

{

log("sprite x = %f, y = %f ", locationInNode.x, locationInNode.y);

log("sprite tag = %d", target->getTag());

target->runAction(ScaleTo::create(0.06f, 1.0f));

}

};

// 添加监听器

EventDispatcher* eventDispatcher = Director::getInstance()->getEventDispatcher();

eventDispatcher->addEventListenerWithSceneGraphPriority(listener, getChildByTag(kBoxA_Tag));

eventDispatcher->addEventListenerWithSceneGraphPriority(listener->clone(), getChildByTag(kBoxB_Tag));

eventDispatcher->addEventListenerWithSceneGraphPriority(listener->clone(), getChildByTag(kBoxC_Tag));

}

比较和下面处理的区别：

void
HelloWorld::onEnter()

{

Layer::onEnter();

log("HelloWorld onEnter");

// 创建一个事件监听器 OneByOne 为单点触摸

auto listener = EventListenerTouchOneByOne::create();

// 设置是否吞没事件，在 onTouchBegan 方法返回 true 时吞没

listener->setSwallowTouches(true);

// onTouchBegan 事件回调函数

listener->onTouchBegan = CC_CALLBACK_2(HelloWorld::touchBegan, this);

// onTouchMoved 事件回调函数

listener->onTouchMoved = CC_CALLBACK_2(HelloWorld::touchMoved, this);

// onTouchEnded 事件回调函数

listener->onTouchEnded = CC_CALLBACK_2(HelloWorld::touchEnded, this);

// 添加监听器

EventDispatcher* eventDispatcher = Director::getInstance()->getEventDispatcher();

eventDispatcher->addEventListenerWithSceneGraphPriority(listener, getChildByTag(kBoxA_Tag));

eventDispatcher->addEventListenerWithSceneGraphPriority(listener->clone(), getChildByTag(kBoxB_Tag));

eventDispatcher->addEventListenerWithSceneGraphPriority(listener->clone(), getChildByTag(kBoxC_Tag));

}

bool
HelloWorld::touchBegan(Touch* touch, Event* event)

{

return false;

}

void HelloWorld::touchMoved(Touch *touch, Event *event)

{

}

void HelloWorld::touchEnded(Touch *touch, Event *event)

{

}