Problems about a sprite in CCMutableArray that cannot runaction after using getObjectAtIndex

Here is some of my code:

CCAction repeat_scale = CCRepeatForever::actionWithActionscale_fade);
sprite~~>runAction;
clickSpriteArray~~>addObject;
Then I use CCSprite
sprite = clickSpriteArray->getObjectAtIndex(0) to get this sprite in another function.
But the sprite I got cannot runAction that has been defined.
Could someone help with this.?