Aligning collection view cells to fit exactly 3 per row

Question

I am trying to make a collection view of images, so that there are 3 per row, with no spacing in between.

My collection view data sources are:

func n         


        

Answer 1

Swift - Version 4.2

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {

    let noOfCellsInRow = 3

    let flowLayout = collectionViewLayout as! UICollectionViewFlowLayout

    let totalSpace = flowLayout.sectionInset.left
        + flowLayout.sectionInset.right
        + (flowLayout.minimumInteritemSpacing * CGFloat(noOfCellsInRow - 1))

    let size = Int((collectionView.bounds.width - totalSpace) / CGFloat(noOfCellsInRow))

    return CGSize(width: size, height: size) 
}