iphone - Why the NSURLConnection connectionDidFinishLoading is not running?

Question

Hello all

My app looks like this:

I have a UIScrollView and there is imageview inside. I implemented the scrollViewDidScroll delegate so that if the scroll did scroll, I will create a NSURLConnection and download a data from some url, for only once.

The problem is that the NSURLConnection connectionDidFinishLoading only be called or run after I release my finger on the scroll view.

To be more clearly, If I use my finger to scroll the scrollview, I confirm that the NSURLConnection is created, but as long as I do not release the scrollview, the connectionDidFinishLoading is never called. Once I release my finger, the delegate of connectionDidFinishLoading is called.

Anyone can explain this to me please?

Thanks