Change button image at runtime in cocos2d

I am creating a button with CCMenuItem in cocos2d. I want the button image to be 开发者_运维技巧change whenever i tap it. Is there anyway to do that at runtime.

Thanks

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When creating a CCMenuItemSprite you can specify normal and selected sprite. Just specify them:

CCMenuItemSprite *item = [CCMenuItemSprite itemFromNormalSprite:@"1.png" selectedSprite:@"2.png" target:self selector:@selector(foo)];