无法在 Collection 视图上获取 indexPath 和选择

Question

我的 collection 视图有问题。我试图选择一个项目的 indexPath 以在点击后显示更多信息，但我无法理解并弄清楚原因。

我尝试允许 collection 查看选择，但没有任何反应。我还尝试在单元格上添加点击手势，但不知道如何从那里获取 indexPath。我在另一个 VC 上添加了相同的代码，其中 collection 视图在整个屏幕上，并且它有效（这里，collection 视图是屏幕的一半）。

这是 collection 视图的（更新的）代码：

class SearchRunnerVC: UIViewController {

    //MARK: - Objects
    var lastNameTextField       = RSTextField(placeholder: "Nom du coureur", returnKeyType: .next,
                                              keyboardType: .default)
    var firstNameTextField      = RSTextField(placeholder: "Prénom", returnKeyType: .next,
                                              keyboardType: .default)
    var numberTextField         = RSTextField(placeholder: "Numéro de dossard", returnKeyType: .next,
                                              keyboardType: .numberPad)
    var raceTextField           = RSTextField(placeholder: "Course", returnKeyType: .done,
                                              keyboardType: .default)

    var searchButton            = RSButton(backgroundColor: .systemPink, title: "Rechercher")
    var collectionView          : UICollectionView! = nil

    var emptyLabel              = UILabel()

    let hud = JGProgressHUD(style: .dark)

    lazy var textFields         = [lastNameTextField, firstNameTextField, numberTextField, raceTextField]

    //MARK: - Properties
    let padding = CGFloat(20)
    let runnersCollection = Firestore.firestore().collection("Runner")
    var runners = [Runner]()

    //MARK: - Lifecycle Methods
    override func viewDidLoad() {
        super.viewDidLoad()
        setupUI()
    }
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        navigationController?.navigationBar.prefersLargeTitles = true
        title = "Rechercher"
    }
}

extension SearchRunnerVC {
    fileprivate func setupUI() {
        configureSuperView()
        configureTextFields()
        configureCollectionView()
        configureButton()
        configureConstraints()
    }

    fileprivate func configureSuperView() {
        view.backgroundColor = .systemBackground
        let viewTap = UITapGestureRecognizer(target: self, action: #selector(hideKeyboard(_:)))
        view.addGestureRecognizer(viewTap)
    }
    fileprivate func configureConstraints() {
        for textField in textFields {
            view.addSubview(textField)

            textField.leftToSuperview(view.leftAnchor, offset: padding)
            textField.rightToSuperview(view.rightAnchor, offset: -padding)
            textField.height(50)

            textField.delegate = self
        }

        firstNameTextField.topToSuperview(view.safeAreaLayoutGuide.topAnchor, offset: padding, usingSafeArea: true)

        lastNameTextField.topToBottom(of: firstNameTextField, offset: padding)

        numberTextField.topToBottom(of: lastNameTextField, offset: padding)

        raceTextField.topToBottom(of: numberTextField, offset: padding)

        searchButton.topToBottom(of: raceTextField, offset: padding)
        searchButton.leftToSuperview(view.leftAnchor, offset: padding)
        searchButton.rightToSuperview(view.rightAnchor, offset: -padding)
        searchButton.height(50)

        collectionView.topToBottom(of: searchButton, offset: padding)
        collectionView.edgesToSuperview(excluding: .top)
    }
    fileprivate func configureTextFields() {
        firstNameTextField.tag  = 0
        lastNameTextField.tag   = 1
        numberTextField.tag     = 2
        raceTextField.tag       = 3
    }
    fileprivate func configureButton() {
        view.addSubview(searchButton)

        searchButton.addTarget(self, action: #selector(searchRunners), for: .touchUpInside)
    }
    fileprivate func createLayout() -> UICollectionViewLayout {
        let itemSize    = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1.0),
                                                 heightDimension: .fractionalHeight(1.0))
        let item        = NSCollectionLayoutItem(layoutSize: itemSize)


        let groupSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1),
                                               heightDimension: .estimated(100))
        let group   = NSCollectionLayoutGroup.horizontal(layoutSize: groupSize, subitem: item, count: 2)
        let spacing = CGFloat(10)
        group.interItemSpacing = .fixed(spacing)


        let section = NSCollectionLayoutSection(group: group)
        section.interGroupSpacing = spacing

        let padding = CGFloat(10)
        section.contentInsets = NSDirectionalEdgeInsets(top: 0, leading: padding, bottom: 0, trailing: padding)

        let headerSize = NSCollectionLayoutSize(widthDimension: .fractionalWidth(1), heightDimension: .estimated(80))
        let header     = NSCollectionLayoutBoundarySupplementaryItem(layoutSize: headerSize, elementKind: UICollectionView.elementKindSectionHeader, alignment: .top)

        section.boundarySupplementaryItems = [header]

        let layout = UICollectionViewCompositionalLayout(section: section)
        return layout
    }
    fileprivate func configureCollectionView() {
        collectionView = UICollectionView(frame: .zero, collectionViewLayout: createLayout())

        collectionView.autoresizingMask = [.flexibleHeight]
        collectionView.backgroundColor  = .systemBackground

        collectionView.delegate     = self
        collectionView.dataSource   = self

        collectionView.register(RunnerCell.self, forCellWithReuseIdentifier: RunnerCell.reuseID)
        collectionView.register(Header.self, forSupplementaryViewOfKind: UICollectionView.elementKindSectionHeader, withReuseIdentifier: Header.reuseID)

        view.addSubview(collectionView)
    }
}


extension SearchRunnerVC : UICollectionViewDelegate, UICollectionViewDataSource {
    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return runners.count
    }

    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        guard let cell = collectionView.dequeueReusableCell(withReuseIdentifier: RunnerCell.reuseID, for: indexPath) as? RunnerCell else { fatalError("Unable to dequeue runner cell")}

        cell.configure(runner: runners[indexPath.row])

        return cell
    }


    func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, at indexPath: IndexPath) -> UICollectionReusableView {
        guard let header = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: Header.reuseID, for: indexPath) as? Header else { fatalError("Unable to dequeue header")}
        header.title.text = "Résultats"
        header.seeButton.addTarget(self, action: #selector(seeAllTapped), for: .touchUpInside)
        header.separator.alpha = 0
        header.backgroundColor = collectionView.backgroundColor
        return header
    }

    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
        print(indexPath.item)
    }
}

Answer 1

不要在单元格上使用点击手势，因为

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath)

完全符合您的期望。问题可能出在您的 collectionView configuration/setup 中。你能展示完整的 ViewController 代码吗？

Answer 2

您的问题似乎与您要添加到 configureSuperView() 中的视图的 UITapGestureRecognizer 有关。通常会触发 collectionView didSelectItemAt... 委托函数的触摸被发送到手势识别器的处理程序，即 hideKeyboard()。

用 view.addGestureRecognizer(viewTap) 注释行，您的代码将起作用。如果是这样，我也可以帮助您实现 hideKeyboard 功能，请告诉我。

无法在 Collection 视图上获取 indexPath 和选择

Cannot get indexPath and selection on Collection View

collectionview

swift