iOS Image Viewer: Set Zoomed Image Back when Scrolling - ios

Question

I have a gallery view that I use to, surprise, view images. :) I wanted it to be very similar to the standard iOS photo app with the same basic functionality: scrolling through images that are zoomable. To do this, I use a regular scroll view which I then populate with other scroll views that contain the images. The basic idea is something like this:
And, I do the populating the following way:
for (int i = 0; i < [imageGalleryArray count]; i++)
{
UIScrollView *imageContainer = [[UIScrollView alloc] initWithFrame:CGRectMake((windowSize.width * i), 0.0f, windowSize.width, windowSize.height)];
imageContainer.contentSize = CGSizeMake(windowSize.width, windowSize.height);
imageContainer.showsHorizontalScrollIndicator = NO;
imageContainer.showsVerticalScrollIndicator = NO;
imageContainer.bouncesZoom = YES;
imageContainer.delegate = self;
imageContainer.minimumZoomScale = 1.0f;
imageContainer.maximumZoomScale = 3.0f;
UIImageView *imageView = [[UIImageView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, windowSize.width, windowSize.height)];
imageView.image = [[imageGalleryArray objectAtIndex:i] objectForKey:#"image"];
imageView.contentMode = UIViewContentModeScaleAspectFit;
imageView.tag = IMAGEZOOMVIEW;
imageView.opaque = YES;
[imageContainer addSubview:imageView];
[galleryScrollView addSubview:imageContainer];
// Add it to array for proper removal later
[contentScrollViewSubviewList addObject:imageContainer];
}
Quite simple and it works fine. The only problem arises when I am zoomed into an image and want to scroll to another. The expected behavior in this case would be to set the zoom level of all images back to their original size. I do this in the scrollViewDidEndDecelerating delegate method like so:
if (scrollView.tag == GALLERYSCROLLVIEW)
{
for (int i = 0; i < [contentScrollViewSubviewList count]; i++)
{
[[contentScrollViewSubviewList objectAtIndex:i] setZoomScale:1.0f animated:YES];
}
}
Unfortunately, it does not work (or rather not as intended). I did some poking around and found out that the image does indeed animate back to its original size when it is the active slide. To elaborate: if I zoom into an image and scroll to another, the image stays zoomed in. When I scroll back to it, that is when it zooms back to its original size. I, however, need the image to scale back as soon as I move away from it ().
just like in the iOS image viewer).
Frankly, I do not understand the whole zoom mechanic enough to find out how to do this properly, and the UIScrollView documentation is of no help either. Could someone show me how to solve my problem?