Setting minimum line spacing in collectionView

Swift 4.2

  func collectionView(_ collectionView: UICollectionView, layout
        collectionViewLayout: UICollectionViewLayout,
                        minimumLineSpacingForSectionAt section: Int) -> CGFloat {

        return 10
    }

Make your UICollectionViewController conform to the protocol UICollectionViewDelegateFlowLayout.

The method you're looking for is:

- (CGFloat)collectionView:(UICollectionView *)collectionView layout:(UICollectionViewLayout*)collectionViewLayout minimumLineSpacingForSectionAtIndex:(NSInteger)section;

Swift:

func collectionView(collectionView: UICollectionView, layout
    collectionViewLayout: UICollectionViewLayout,
    minimumLineSpacingForSectionAtIndex section: Int) -> CGFloat {
        return 1.0
}