cocos2d-x之为label添加事件监听器，单点触摸

在bool HelloWorld::init()
 1 //获取可见区域的大小
 2     Size visibleSize = Director::getInstance()->getVisibleSize();
 3     //定义一个文本，显示内容
 4     auto label = LabelTTF::create("Chick me", "Courier", 30);
 5     //定义label的位置
 6     label->setPosition(Point(visibleSize.width/2,visibleSize.height/2));
 7     addChild(label);//将label添加进去
 8     //EventListenerTouchOneByOne表示一个接一个的触发，每次触摸只能监听到一个触摸点
 9     auto listener = EventListenerTouchOneByOne::create();
10     //onTouchBegan表示开始触摸的事件
11     listener->onTouchBegan = [](Touch *t, Event *e){
12         
13         log("onTouchBegan");
14         
15         return false;
16     };
17     //getEventDispatcher获取事件的派发器，
18     //addEventListenerWithSceneGraphPriority(事件, 节点);添加事件监听器
19     Director::getInstance()->getEventDispatcher()->addEventListenerWithSceneGraphPriority(listener, label);