Possible memory leak in CCLayer when using accelerometer (iOS)?

cocos2d-x C++
#1

Hi,
When I register my layer using setIsAccelerometerEnabled, CCNode:m_uReference is not being decreased when transacting to a new scene with ::replaceScene.
This in turn causes the CCLayer dtor not to be called.
I think that the problem (and fix?) is showed below.

@implementation AccelerometerDispatcher
...
- (void) removeDelegate: (cocos2d::CCAccelerometerDelegate *) delegate
{
out ==>  [delegateWrappers removeObject:[self findDelegateWrapperByDelegate:delegate]];

in <==    id ptr = [self findDelegateWrapperByDelegate:delegate];
in <==    [delegateWrappers removeObject:ptr];
in <==    [ptr release];
}
...
@end

and also in CCLayer.cpp:

void CCLayer::onEnterTransitionDidFinish()
{
out==>    if (m_bIsAccelerometerEnabled)
out==>    {
out==>        CCAccelerometer::sharedAccelerometer()->addDelegate(this);
out==>    }

    CCNode::onEnterTransitionDidFinish();
}

Or maybe I am doing something wrong?

Thanks.

#2

Please try to call layer->setIsAccelerometerEnabled(false) before the transition, do this will remove the accelerometer delegate from AccelerometerDispatcher.

#3

I think that there is double memory leak, because CCLayer::onEnter adds one reference to layer:

void CCLayer::onEnter()
{
    // register 'parent' nodes first
    // since events are propagated in reverse order
    if (m_bIsTouchEnabled)
    {
        this->registerWithTouchDispatcher();
    }

    // then iterate over all the children
    CCNode::onEnter();

    // add this layer to concern the Accelerometer Sensor
    if (m_bIsAccelerometerEnabled)
    {
        CCAccelerometer::sharedAccelerometer()->addDelegate(this);
    }...

onEnterTransitionDidFinish adds second reference to layer:

void CCLayer::onEnterTransitionDidFinish()
{
    if (m_bIsAccelerometerEnabled)
    {
        CCAccelerometer::sharedAccelerometer()->addDelegate(this);
    }...

while onExit doesn’t remove any reference - removeDelegate is called - it’s ok, but it doesn’t decrease reference count

void CCLayer::onExit()
{
    if( m_bIsTouchEnabled )
    {
        CCTouchDispatcher::sharedDispatcher()->removeDelegate(this);
    }

    // remove this layer from the delegates who concern Accelerometer Sensor
    if (m_bIsAccelerometerEnabled)
    {
        CCAccelerometer::sharedAccelerometer()->removeDelegate(this);
    }...

… tested with version cocos2d-1.0.0-x-0.9.0 (ios version - Xcode)

…AccelerometerDestroy that decreases reference count is called in “dealloc” function of AccelerometerDelegateWrapper, but it isn’t probably called at all…
How to fix it?

#4

Hi,
I tried to run the accelerometer test with instruments and it detected a leak after the test exits to the main menu. Bug?

#5

Hi, all. So sorry for that. It’s a bug here, #675 created.