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从多节UITableView中的UITableViewCell获取IndexPath以响应通知

indexpath uitableview swift ios

Vinícius Barcelos · 技术社区 · 6 年前

我有一个包含多个部分的tableView,我想在一个单元格中(通过通知)显示Alamofire正在处理的下载进度。

现在,我已经有了一个通知贴,作为信息,一个事件对象工作和传递,如下所示:

let info = ["episode": episode, "progress": progress.fractionCompleted] as [String : Any]
NotificationCenter.default.post(name: .downloadProgress, object: nil, userInfo: info)

我不知道如何在我的单元格中循环找到哪一个有那个插曲,然后得到它的索引,这样我就可以正确地响应通知了。

我试图获取作为数据源的数组的索引,但是由于tableView有多个部分,因此无法工作。

有人能帮我吗?谢谢

我的TableViewController:

//
//  EpisodesViewController.swift
//  Podee
//
//  Created by VinÃcius Barcelos on 21/07/18.
//  Copyright Â© 2018 VinÃcius Barcelos. All rights reserved.
//

import UIKit
import RealmSwift
import Kingfisher

class EpisodesTableViewController: UITableViewController {

    //MARK:- Variables
    var episodes: Results<Episode> = RealmService.shared.read(object: Episode.self).sorted(byKeyPath: "pubDate", ascending: true)
    let episodesCellId = "episodesCellId"
    var notificationToken: NotificationToken?

    var episodesDictionary = Dictionary<Date, [Episode]>()
    var dateDays = [Date]()

    //MARK:- Lifecycle
    override func viewDidLoad() {
        super.viewDidLoad()
        setupTableView()
        setupObservers()
    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        tableView.reloadData()
    }

    deinit {
        self.notificationToken?.invalidate()
        //NotificationCenter.default.removeObserver(self, name: NSNotification.Name.downloadProgress, object: nil)
    }


    //MARK:- Setup
    fileprivate func setupObservers() {
        NotificationCenter.default.addObserver(self, selector: #selector(handleDownloadProgressNotification(notification:)), name: .downloadProgress, object: nil)
        }
    }

    @objc func handleDownloadProgressNotification(notification:Notification) {
        ////////
    }


    //MARK:- Tableview methods
    override func numberOfSections(in tableView: UITableView) -> Int {
        return episodesDictionary.count
    }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        let key = dateDays[section]
        guard let datesValues = episodesDictionary[key] else {
            return 0
        }
        return datesValues.count
    }

    override func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = "dd MMMM"
        return dateFormatter.string(from: dateDays[section])
    }

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: episodesCellId, for: indexPath) as! EpisodesTableViewCell

        let key = dateDays[indexPath.section]

        if let podcastValues = episodesDictionary[key] {
            cell.delegate = self
            cell.progressBar.isHidden = true
            cell.episode = podcastValues[indexPath.row]
        }
        return cell
    }

}

// Start download
        Alamofire.request(episode.streamURL).downloadProgress { (progress) in
        // Send a notification about the download progress
        let info = ["episode": episode, "progress": progress.fractionCompleted] as [String : Any]
        NotificationCenter.default.post(name: .downloadProgress, object: nil, userInfo: info)
        //print(progress)
        // Check data
    }.responseData { (responseData) in ......

1 回复 | 直到 6 年前

Sahil Manchanda 6 年前

修改下载功能并添加以下参数

 func downloadFile(url: String,date: Date, index: Int){
        let utilityQueue = DispatchQueue.global(qos: .utility)
        Alamofire.download(url)
            .downloadProgress(queue: utilityQueue) { progress in
                let info: [String: AnyHashable] = ["date": date,
                             "index" : index,
                             "progress": progress.fractionCompleted
                ]
                NotificationCenter.default.post(name: .downloadProgress, object: nil, userInfo: info)
            }
            .responseData { response in
              ......  
        }
    }

在viewcontroller中,将函数替换为以下代码:

@objc func handleDownloadProgressNotification(notification:Notification) {
        var dateDays = [Date]()
        guard let info = notification.userInfo,
        let date = info["date"] as? Date,
        let index = info["index"] as? Int,
        let progress = info["progress"] as? Double,
        let section = dateDays.index(where: {$0 == date})
        else {return}

        let indexPath = IndexPath(item: index, section: section)

    }