ios - collectionView分为三行swift 4

Question

我需要创建一个collectionView来显示一系列图像，分别为每张照片。我正在尝试重现您在图片中看到的内容，查看照片，然后向左或向右滚动查看下一张照片。我无法创建 collectionView

的布局

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    return self.datasource.count
}

//UICollectionViewDelegateFlowLayout - constraint della collecion view da innestare
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
    let width = (UIScreen.main.bounds.size.width - 3) / 3
    let height = width
    return CGSize(width: width, height: height)
}

Answer 1

swift 4:

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

     //calculation of cell size
    return CGSize(width: self.collectionview.frame.size.width,height: 180)
      }

  func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
    // indentation 
    return UIEdgeInsetsMake(0, 23, 20, 20)
    }

如果你想水平或垂直拖动，在collectionview中有一个“滚动方向”属性。您可以将其更改为水平或垂直。