cocos2d中各种setTouchPriority无效的问题

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CCTouchDispatcher中是这样分发触摸事件的：

CCARRAY_FOREACH(m_pTargetedHandlers,pObj)//这里是遍历了一个注册过触摸事件的数组，按优先级排序
            {
                pHandler = (CCTargetedTouchHandler *)(pObj);

                if (! pHandler)
                {
                   break;
                }

                bool bClaimed = false;
                if (uIndex == CCTOUCHBEGAN)
                {
                    bClaimed = pHandler->getDelegate()->ccTouchBegan(pTouch,pEvent);

                    if (bClaimed)
                    {
                        pHandler->getClaimedTouches()->addObject(pTouch);
                    }
                } else
                if (pHandler->getClaimedTouches()->containsObject(pTouch))
                {
                    // moved ended canceled
                    bClaimed = true;

                    switch (sHelper.m_type)
                    {
                    case CCTOUCHMOVED:
                        pHandler->getDelegate()->ccTouchMoved(pTouch,pEvent);
                        break;
                    case CCTOUCHENDED:
                        pHandler->getDelegate()->ccTouchEnded(pTouch,pEvent);
                        pHandler->getClaimedTouches()->removeObject(pTouch);
                        break;
                    case CCTOUCHCANCELLED:
                        pHandler->getDelegate()->ccTouchCancelled(pTouch,pEvent);
                        pHandler->getClaimedTouches()->removeObject(pTouch);
                        break;
                    }
                }

                if (bClaimed && pHandler->isSwallowsTouches())
                {
                    if (bNeedsMutableSet)
                    {
                        pMutableTouches->removeObject(pTouch);
                    }

                    break;
                }
            }

然后如果调用这里的 setPriority，就会重新排序数组： rearrangeHandlers

void CCTouchDispatcher::setPriority(int nPriority,CCTouchDelegate *pDelegate)
{
    CCAssert(pDelegate != NULL,"");

    CCTouchHandler *handler = NULL;

    handler = this->findHandler(pDelegate);

    CCAssert(handler != NULL,"");
	
    if (handler->getPriority() != nPriority)
    {
        handler->setPriority(nPriority);
        this->rearrangeHandlers(m_pTargetedHandlers);
        this->rearrangeHandlers(m_pStandardHandlers);
    }
}

但是在业务层调用的 setPriority是这样的：

void CCTouchHandler::setPriority(int nPriority)
{
    m_nPriority = nPriority;
}

所以你会发现如果在初始化一个控件的时候调用 setPriority就会有效，而在运行中动态更改就无效，就是因为初始化后的下一帧调用（调用onEnter时,会注册touchdelegate）会根据当前priority将其注册进那个数组：

void CCTouchDispatcher::forceAddHandler(CCTouchHandler *pHandler,CCArray *pArray)
{
    unsigned int u = 0;

    CCObject* pObj = NULL;
    CCARRAY_FOREACH(pArray,pObj)
     {
         CCTouchHandler *h = (CCTouchHandler *)pObj;
         if (h)
         {
             if (h->getPriority() < pHandler->getPriority())
             {
                 ++u;
             }
 
             if (h->getDelegate() == pHandler->getDelegate())
             {
                 CCAssert(0,"");
                 return;
             }
         }
     }

    pArray->insertObject(pHandler,u);
}

所以，改变触摸分发数组的机会只有一次，之后如果想动态的改变优先级需要获取 TouchDispatcher后设置，或者类似menu可以调用现成的函数 setHandlerPriority

cocos2d中 各种setTouchPriority无效的问题

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cocos2d中各种setTouchPriority无效的问题