title: Change the background image in cocos2d
body: <p>I am making a game using cocos2d. in that I want to change the background after each second of time.
  I don't know how to do this in cocos2d. I am having 15 different images and one by one each image will be shown, i.e. after1 second next image will appear.</p>
  
  <p>I am new to cocos2d so, If any one can help me???</p>
  
  <p>thank you in advance to all.</p>