UIImageView in UIScrollView

I have a series of UIImageViews in a UIScrollView. The user can zoom into each one,开发者_开发百科 but after a bit of usage the images start disappearing, and then various images in the app disappear. I'm wondering if anybody has any any experience with this and has any idea why this could be happening?

Its a complete guess until you give us source, but chances are that you are doing something like not retaining your image views or are adding them to another view – effectively removing them from the first view they were in.