Landscape orientation for Collection View in Swift

Question

I am encountering a problem on landscape orientation for my collection view cell. When the app is in portrait it gives me the correct number of cell per row which is 2. But when

Answer 1

Swift 5

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
    var flag:CGSize? = nil
    if UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiom.pad
    {
        if UIApplication.shared.statusBarOrientation.isPortrait{

            let cellWidth = floor((collectionView.bounds.width - 5) / 2)
            flag = CGSize(width: cellWidth, height: cellWidth)
        }

        else if UIApplication.shared.statusBarOrientation.isLandscape{

            let cellwidth = floor((collectionView.bounds.width - 5) / 4)
            flag =  CGSize(width: cellwidth, height: cellwidth)

        }

    }
    else if UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiom.phone{

        if UIApplication.shared.statusBarOrientation.isLandscape {
          let cellWidth = floor((collectionView.bounds.width - 5) / 2)
            flag = CGSize(width: cellWidth, height: cellWidth)
        } else if UIApplication.shared.statusBarOrientation.isPortrait{
            //  let cellWidth = floor((collectionView.bounds.width - 5))
            flag = CGSize(width: 402 , height: 185)
        }

    }

    return flag!
}