How to change delay during animate?

cocos2d-x C++
#1

Hi Everyone.

I’m developing with cocos2d-x-2.0.

I want to change delay during animate after define animation delay.

My method

//Define Animation.
CCAnimation animation = CCAnimation::animationWithSpriteFrames;
CCAnimationCache::sharedAnimationCache~~>addAnimation;
CCFiniteTimeAction* action = CCRepeatForever::actionWithAction);
img~~>runAction;
void Game::update
{
//change animation delay
CCAnimationanimation = CCAnimationCache::sharedAnimationCache()>animationByName;
animation>setDelayPerUnit(0.2f);

}

setDelayPerUnit method is not change animation delay.
How to change delay during animate?