UIScrollView change pages after animation

Question

Ok, I have a complicated scenario here. I have a scrollview which scrolls horizontally and contains tiles, 1 centered on the screen at a time with the user still able to see if there are more to the left or right by way of having the edges of the 2 views visible on either side. I am able to add the views programmatically to the scrollview and have paging work properly, so the user can swipe back and forth between them. Another requirement is to have an initial animation where the first view slides in, then is bounced off to the left by the second view. I accomplished this by using a series of UIView animations, and it works well.

Here is my problem: After the animation completes, you cannot scroll left to get to the first UIView that was created. I suspect that this is because it was animated out to the left of the content area of the scrollview. I have tried to increase the contentSize of the scrollview, but I still get the same behavior.Once the initial scrollview has been moved off to the left, I cannot swipe to page to it.

Is there a common pattern I could use to accomplish this in a better way?

Answer 1

It sounds to me like you're animating the child view's frame to the left so that the x coordinate of that first view's frame is negative, instead of animating the scroll view's contentOffset to the right. If that's the case, is there a reason you aren't just setting the scroll view's contentOffset inside an animation block? If there is a reason, what if after the animation completes you "fix up" the content offset and the frames of the child views so that none of the views are in a negative position.

But, I guess I have more questions than answers right now, so it might help to post the code showing how you do your animations to make it easier to answer your question.