基于RxSwift的TableView自定义滑动收藏动作：如何获取行数据？

现有代码实现 #

ViewModel中的news变量 #

var news = PublishSubject<[Article]>()

HomeViewController的RxSwift扩展 #

extension HomeViewController {
    func designTableView() {
        newsTable.separatorStyle = .none
        newsTable.showsVerticalScrollIndicator = false
    }

    func createCellView() {
        homeViewModel.news.bind(to: newsTable.rx.items(cellIdentifier: "cell", cellType: NewsCell.self)) { _, news, cell in
            cell.newsTitle.text = news.title
            cell.newsImage?.sd_setImage(with: URL(string: news.urlToImage ?? ""), placeholderImage: UIImage(systemName: "photo"))
        }.disposed(by: disposeBag)
    }

    func whenNewsSelected() {
        newsTable.rx.modelSelected(Article.self).bind { article in
            let vc = self.storyboard?.instantiateViewController(withIdentifier: "NewsDetail") as? NewsDetails
            vc?.article = article
            self.navigationController?.pushViewController(vc!, animated: true)
        }.disposed(by: disposeBag)
    }

    func setDelegateForTableView() {
        newsTable.rx.setDelegate(self).disposed(by: disposeBag)
    }
}

遇到的问题 #

我想给Cell添加收藏动作，已经写了侧滑操作的代码，但不知道怎么获取当前行对应的新闻数据：

func tableView(_ tableView: UITableView,
               trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath) -> UISwipeActionsConfiguration?
{
    let FlagAction = UIContextualAction(style: .normal, title: "Fav", handler: { (_: UIContextualAction, _: UIView, success: (Bool) -> Void) in
        print("osman")
        success(true)
    })
    FlagAction.backgroundColor = .orange

    return UISwipeActionsConfiguration(actions: [FlagAction])
}

解决方案 #

方式一：利用RxSwift内置的model(at:)方法 #

RxSwift的TableView扩展提供了直接通过indexPath获取对应模型的方法，在侧滑的handler里这样用：

func tableView(_ tableView: UITableView,
               trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath) -> UISwipeActionsConfiguration?
{
    let flagAction = UIContextualAction(style: .normal, title: "Fav", handler: { [weak self] (_, _, success) in
        guard let self = self else {
            success(false)
            return
        }
        // 获取对应行的Article模型
        guard let article = try? tableView.rx.model(at: indexPath) as Article else {
            success(false)
            return
        }
        // 这里写你的收藏逻辑，比如存到本地数据库或者调用收藏API
        print("收藏文章：\(article.title ?? "无标题")")
        success(true)
    })
    flagAction.backgroundColor = .orange

    return UISwipeActionsConfiguration(actions: [flagAction])
}

注意加上[weak self]避免循环引用，用try?处理可能的索引越界等错误情况。

方式二：在ViewModel中维护数据源数组 #

如果希望更直接地访问数据，可以在ViewModel里额外维护一个当前显示的数组，同步更新：

// ViewModel中添加
var currentArticles: [Article] = []

// 假设你有获取新闻的方法，更新数据时同步赋值
func fetchNews() {
    // 模拟获取到新闻数据
    let fetchedArticles: [Article] = ...
    currentArticles = fetchedArticles
    news.onNext(fetchedArticles)
}

然后在侧滑方法里直接通过indexPath访问：

func tableView(_ tableView: UITableView,
               trailingSwipeActionsConfigurationForRowAt indexPath: IndexPath) -> UISwipeActionsConfiguration?
{
    let flagAction = UIContextualAction(style: .normal, title: "Fav", handler: { [weak self] (_, _, success) in
        guard let self = self, indexPath.row < self.homeViewModel.currentArticles.count else {
            success(false)
            return
        }
        let article = self.homeViewModel.currentArticles[indexPath.row]
        // 处理收藏逻辑
        print("收藏文章：\(article.title ?? "无标题")")
        success(true)
    })
    flagAction.backgroundColor = .orange

    return UISwipeActionsConfiguration(actions: [flagAction])
}

内容的提问来源于stack exchange，提问作者themmfa