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- Make UICollectionView zoomable? 1 answer
I am confused. I have a UICollectionView. I have my own UICollectionViewLayout subclass (iow, I am not using the Flow thing). UICollectionView instance is a subclass of UIScrollView. It adds multiple subviews. But questions like Properly zooming a UIScrollView that contains many subviews seem to say that scrollable views should just have one subview to "scroll the whole view". Seems kind of an inconsistent marriage to me. I mean why does Apple give me a framework for making a multiple child view, and then stick them all in scroll view, which isn't supposed to work well?
So I'm curious how I should go about making my whole UICollectionView (it's in a UICollectionViewController subclass) zoomable. Do I need to implement various delegate methods and invalidate/manipulate the layout object, deriving the layouts based on some property I keep in my layout? Or is there some other mechanism?
Aside, why can't it just manipulate the zoomScale property and do it automagically for me? Or am I missing some subtlety here?
I am not sure whether I got your question in correct way or not, but I think you might want to check these links:-
1. zoom entire UICollectionView - It also has a link to Sample code for UICollectionView. You might be interested in checking it.
2. Adding pinch zoom to a UICollectionView.
3. Make UICollectionView zoomable?
Hope this will help you.
If you're looking for the iOS 7 Photos application type of pinching + transition, maybe take a look at this question here: UICollectionView interactive layout transition using iOS 7 APIs
来源：https://stackoverflow.com/questions/22182657/how-to-enable-zoom-for-uicollectionview