Cocos2D, UIScrollView, and initial placement of a scene

I am using a UIScrollView to forward touches to Cocos2D as outlined in http://getsetgames.com/2009/08/21/cocos2d-and-uiscrollview/

Everything works great 开发者_JAVA技巧after a few days of working with it, except one thing: when the initial view appears on the screen, the background appears to be scrolled to the center. As soon as I try to scroll around, the image jumps to 0,0, and everything works as normal, except the touches are offset by half the width and height of the background image. Am I overlooking something basic? I can't think of a useful portion of the code that illustrates the issue, as I can't track it down, but would be happy to post code if anyone has any ideas.

Thanks in advance,

-Roberto

I just had to localize the touches in respect to the window, by using nil in locationInView. This returns the touch's location on what's currently visible in the display.

CGPoint location = [[CCDirector sharedDirector] convertToGL:[touch locationInView:nil]];