分组样式设置不受IB,UITableView的影响

import UIKit
import UICollectionView

let flowLayout = UICollectionViewFlowLayout()
flowLayout.scrollDirection = .vertical
flowLayout.minimumLineSpacing = 10
flowLayout.minimumInteritemSpacing = 10
flowLayout.sectionInset = UIEdgeInsets(top: 10, left: 10, bottom: 10, right: 10)

let collectionView = UICollectionView(frame: CGRect.zero, collectionViewLayout: flowLayout)

collectionView.dataSource = self
collectionView.delegate = self

func numberOfSections(in collectionView: UICollectionView) -> Int {
    // 返回所需的分组数
}

func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    // 返回每个分组中的单元格数
}

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    // 返回一个自定义单元格实例，其中包含您的数据
}

func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, at indexPath: IndexPath) -> UICollectionReusableView {
    // 返回一个自定义头部或尾部视图，如果需要的话
}

view.addSubview(collectionView)
collectionView.translatesAutoresizingMaskIntoConstraints = false
NSLayoutConstraint.activate([
    collectionView.topAnchor.constraint(equalTo: view.topAnchor),
    collectionView.bottomAnchor.constraint(equalTo: view.bottomAnchor),
    collectionView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
    collectionView.trailingAnchor.constraint(equalTo: view.trailingAnchor)
])