MyBigFish

// NOTE: This delegate method requires you to disable UICollectionView's `pagingEnabled` property.
- (void)scrollViewWillEndDragging:(UIScrollView *)scrollView
                     withVelocity:(CGPoint)velocity
              targetContentOffset:(inout CGPoint *)targetContentOffset {
 
  CGPoint point = *targetContentOffset;  

  UICollectionViewFlowLayout *layout = (UICollectionViewFlowLayout *)self.collectionView.collectionViewLayout;
 
  // This assumes that the values of `layout.sectionInset.left` and