Bug: CCScheduler#scheduleSelector. Selector already scheduled. Updating interval from: 0.0000 to 0.0000

原因是当前的scheduleOnce还没有执行完成,

可以将scheduleOnce方法改写成另外一种形式，把CCDelayTime和CCCallFunc拼接构造延迟事件调用:

CCDelayTime * delayAction = CCDelayTime::create(dt);  
CCCallFunc * callFunc = CCCallFunc::create(pSelectorTarget, selector);  
this->runAction(CCSequence::createWithTwoActions(delayAction, callFunc));