ios - UICollectionView 单元格部分可见

Question

我想制作一个可以水平滚动的collectionView，并且只有一个单元格项目可见，一个单元格项目部分可见。单元格应占据 collectionView 的整个高度。

我玩过collectionView的sectionInset。但没能达到我的目标。

我的代码:

import UIKit

class BooksController: UIViewController {

    @IBOutlet weak var booksCollectionView: UICollectionView!

    override func viewDidLoad() {
        super.viewDidLoad()


        let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
        layout.sectionInset = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 20)
        layout.itemSize = CGSize(width: booksCollectionView.frame.width, height: booksCollectionView.frame.height)
        layout.minimumInteritemSpacing = 10
        layout.minimumLineSpacing = 10
        layout.scrollDirection = .horizontal
        booksCollectionView.collectionViewLayout = layout


        booksCollectionView.register(UINib(nibName: "BookCell", bundle: .main), forCellWithReuseIdentifier: "BookCell")
        booksCollectionView.dataSource = self
        booksCollectionView.delegate = self
        // Do any additional setup after loading the view.
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


    /*
    // MARK: - Navigation

    // In a storyboard-based application, you will often want to do a little preparation before navigation
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        // Get the new view controller using segue.destinationViewController.
        // Pass the selected object to the new view controller.
    }
    */

}

extension BooksController: UICollectionViewDataSource {
    func numberOfSections(in collectionView: UICollectionView) -> Int {
        return 1
    }

    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return 10
    }

    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        if let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "BookCell", for: indexPath) as? BookCell {
            return cell
        }
        return UICollectionViewCell()
    }
}

extension BooksController: UICollectionViewDelegate, UICollectionViewDelegateFlowLayout {
//    func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAtIndex section: Int) -> UIEdgeInsets {
//        return UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 20)
//    }
}

目标(类似于此处的collectionView)

我的输出

Answer 1

使用这段代码

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
        let width = self.view.frame.width - 100
        let height = self.view.frame.height
        return CGSize(width: width, height: height)
    }

不要忘记添加此委托(delegate)

UICollectionViewDelegateFlowLayout