CCLayer setTouchPriority has no effect

Question

I created a Layer, which has a sole purpose to block ("swallow") touches, and this feature can be turned on and off. The class is very basic, if it receives the touch it always swallows it:

bool BlockingLayer::init(){

    // Super init.
    if ( !CCLayer::init() )
    {
        return false;
    }

    setTouchEnabled(true);
    setTouchMode(kCCTouchesOneByOne);
    setTouchPriority(INT_MAX);

    return true;
}



bool BlockingLayer::ccTouchBegan(CCTouch *pTouch, CCEvent *pEvent)
{
    CCLOG("BlockingLayer swallowed touch!");
    return true;
}

So by default it has a really bad priority, it receives touches if no other class claimed it. But in the scene where I am using this layer I would like to set it to a different priority when certain events occur:

bool MyScene::init(int unitNumber, CCString* path){
    // Super init.
    ...
    _blockingLayer = BlockingLayer::create();
    this->addChild(_blockingLayer);

    return true;
}

bool MyScene::ccTouchBegan(CCTouch *pTouch, CCEvent *pEvent){
     _blockingLayer->setTouchPriority(INT_MIN);
     ...
}

Now the layer should have the best priority possible, so it should swallow all touches. But it does not, its behaviour does not change. I see its registerWithTouchDispatcher() called and the m_nTouchPriority changed correctly. BUT the layer's behaviour is unchanged.

This is on Cocos2D-x 2.2. Any help is appreciated.

Answer 1

Turns out this was a bug in Cocos2d-x:

see this:

https://github.com/cocos2d/cocos2d-x/pull/5641

Solution:

change in CCTouchDispatcher.cpp this:

void CCTouchDispatcher::addStandardDelegate(CCTouchDelegate *pDelegate, int nPriority)
{    
    CCTouchHandler *pHandler = CCStandardTouchHandler::handlerWithDelegate(pDelegate, nPriority);
    if (! m_bLocked)
    {
        forceAddHandler(pHandler, m_pStandardHandlers);
    }
    else
    {
        /* If pHandler is contained in m_pHandlersToRemove, if so remove it from     m_pHandlersToRemove and return.
         * Refer issue #752(cocos2d-x)
         */
         if (ccCArrayContainsValue(m_pHandlersToRemove, pDelegate))
         {
             ccCArrayRemoveValue(m_pHandlersToRemove, pDelegate);
             return;
          }

        m_pHandlersToAdd->addObject(pHandler);
        m_bToAdd = true;
    }
}

and

void CCTouchDispatcher::addTargetedDelegate(CCTouchDelegate *pDelegate, int nPriority, bool bSwallowsTouches)
{    
    CCTouchHandler *pHandler = CCTargetedTouchHandler::handlerWithDelegate(pDelegate, nPriority, bSwallowsTouches);
    if (! m_bLocked)
    {
        forceAddHandler(pHandler, m_pTargetedHandlers);
    }
    else
    {
        /* If pHandler is contained in m_pHandlersToRemove, if so remove it from m_pHandlersToRemove and return.
         * Refer issue #752(cocos2d-x)
         */
         if (ccCArrayContainsValue(m_pHandlersToRemove, pDelegate))
          {
              ccCArrayRemoveValue(m_pHandlersToRemove, pDelegate);
              return;
          }

        m_pHandlersToAdd->addObject(pHandler);
        m_bToAdd = true;
    }
}

to this:

void CCTouchDispatcher::addStandardDelegate(CCTouchDelegate *pDelegate, int nPriority)
{    
    CCTouchHandler *pHandler = CCStandardTouchHandler::handlerWithDelegate(pDelegate, nPriority);
    if (! m_bLocked)
    {
        forceAddHandler(pHandler, m_pStandardHandlers);
    }
    else
    {
        /* If pHandler is contained in m_pHandlersToRemove, if so remove it from m_pHandlersToRemove and return.
         * Refer issue #752(cocos2d-x)
         */
        if (ccCArrayContainsValue(m_pHandlersToRemove, pDelegate))
        {
            CCTouchHandler *pOldHandler = findHandler(pDelegate);
            if (pOldHandler && pOldHandler->getPriority() == nPriority)
            {
                ccCArrayRemoveValue(m_pHandlersToRemove, pDelegate);
                return;
            }
        }

        m_pHandlersToAdd->addObject(pHandler);
        m_bToAdd = true;
    }
}

and

void CCTouchDispatcher::addTargetedDelegate(CCTouchDelegate *pDelegate, int nPriority, bool bSwallowsTouches)
{    
    CCTouchHandler *pHandler = CCTargetedTouchHandler::handlerWithDelegate(pDelegate, nPriority, bSwallowsTouches);
    if (! m_bLocked)
    {
        forceAddHandler(pHandler, m_pTargetedHandlers);
    }
    else
    {
        /* If pHandler is contained in m_pHandlersToRemove, if so remove it from m_pHandlersToRemove and return.
         * Refer issue #752(cocos2d-x)
         */
        if (ccCArrayContainsValue(m_pHandlersToRemove, pDelegate))
        {
            CCTouchHandler *pOldHandler = findHandler(pDelegate);
            if (pOldHandler && pOldHandler->getPriority() == nPriority)
            {
                ccCArrayRemoveValue(m_pHandlersToRemove, pDelegate);
                return;
            }
        }

        m_pHandlersToAdd->addObject(pHandler);
        m_bToAdd = true;
    }
}

Answer 2

In addTargetedDelegate() set the third param to true

 bool BlockingLayer::init(){

    // Super init.
    if ( !CCLayer::init() )
    {
        return false;
    }

    setTouchEnabled(true);
    setTouchMode(kCCTouchesOneByOne);
    setTouchPriority(INT_MAX);

    return true;
}

void BlockingLayer::onEnter()
{
    CCDirector::sharedDirector()->getTouchDispatcher()->addTargetedDelegate(this, INT_MAX, true);  //<---- Param (target, touchPriority, isSwallowTouches )
    CCNode::onEnter();
}

void BlockingLayer::onExit()
{
     CCDirector::sharedDirector()->getTouchDispatcher()->removeDelegate( this );
     CCNode::onExit();
}


bool BlockingLayer::ccTouchBegan(CCTouch *pTouch, CCEvent *pEvent)
{
    CCLOG("BlockingLayer swallowed touch!");
    return true;
}