在开始直播后获取 UITableView 以刷新用户

Question

我正在开发的应用程序的登录页面有一个以应用程序命名的占位符头像，当没有用户主动直播时（为此使用 Red5 Pro 流媒体框架），该头像就会出现。

但是当有人开始直播时，我希望它自动刷新表格视图并显示新用户的头像。到目前为止，我所写的内容是可行的，但不完全是。当有人开始直播时，占位符头像会消失，但正在直播的用户头像不会出现。

如果我关闭应用程序并重新打开它，它会正确显示。这是我在 Swift 中的代码 3，我做错了什么？是否应该将刷新调用移出 ViewDidLoad？我是否错误地使用了 Dispatch Queue？谢谢

import UIKit
import Firebase

class HomeController: UIViewController, UITableViewDataSource,     UITableViewDelegate, cellDelegate {

@IBOutlet var tableView: UITableView!
var stream: String!
var top: [SSStream] = []
var recent: [SSStream] = [SSStream()]
var trending: [SSStream] = [SSStream()]
var ref: FIRDatabaseReference!

override func viewDidLoad() {
    navigationItem.title = "Swiffshot"
    navigationController?.navigationBar.isTranslucent = false
    let settings = UIButton(frame: CGRect(x: 0, y: 0, width: 20, height: 20))
    settings.setImage(#imageLiteral(resourceName: "Settings"), for: .normal)
    settings.addTarget(self, action: #selector(settingsPressed), for: .touchUpInside)
    navigationItem.leftBarButtonItem = UIBarButtonItem(customView: settings)
    let friends = UIButton(frame: CGRect(x: 0, y: 0, width: 23, height: 20))
    friends.setImage(#imageLiteral(resourceName: "AllFriends"), for: .normal)
    friends.addTarget(self, action: #selector(friendsPressed), for: .touchUpInside)
    navigationItem.rightBarButtonItem = UIBarButtonItem(customView: friends)

    let nib = UINib(nibName: "MainHeader", bundle: Bundle.main)
    tableView.register(nib, forHeaderFooterViewReuseIdentifier: "MainHeader")

    ref = FIRDatabase.database().reference()


    if !SSContact.shared.active {
        performSegue(withIdentifier: "fromMainToAuth", sender: self)
    }

    SSContact.shared.load() { SSContact.shared.propertyCheck(self) { } }

//        SSContact.shared.subscribeToTop(pulse: { (streams) in
//            self.top.removeAll()
//            self.top.append(contentsOf: streams)
//            self.tableView.reloadSections(IndexSet(integer: 0), with:     .automatic)
//        })

    ref.child("streams").observe(.value, with: { (snapshot) in

        print("I ran")

        self.top.removeAll()
        if let userData = snapshot.value as? NSDictionary {
            for stream in userData {
                let newStream = SSStream()
                newStream.username = stream.key as! String
                print("Found stream \(stream.key as! String)")
                newStream.isPrivate = !((stream.value as! NSDictionary)["public"] as! Bool)
                newStream.views = (stream.value as! NSDictionary)["views"] as! Int
                newStream.isEnabled = true
                self.top.append(newStream)
            }
        }
        if self.top.isEmpty {
            print("No Streams Found")
            self.top.append(SSStream())
        }
        DispatchQueue.main.async {
            self.tableView.reloadSections(IndexSet(integer: 0), with: .automatic)
            self.tableView.reloadData()
        }
    })
}

func cellGotPressed(_ stream: String) {
    self.stream = stream
    performSegue(withIdentifier: "toPlayer", sender: self)
}

func settingsPressed() {
    performSegue(withIdentifier: "toSettings", sender: self)
}

func friendsPressed() {
    performSegue(withIdentifier: "fromMainToExpandable", sender: self)
}

func cameraTapped() {
    performSegue(withIdentifier: "toRed", sender: self)
}

func cellTapped() {
    print("Cell Tapped")
}

// MARK: Segue

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if segue.identifier == "toPlayer" {
        let player = segue.destination as! VideoPlayerViewController
        player.isSubscribing = true
        player.stream = stream
    }
}

// MARK: Table View Functions

func numberOfSections(in tableView: UITableView) -> Int {
    return 3
}

func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return 1
}

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    if indexPath.section == 0 {
        let cell = tableView.dequeueReusableCell(withIdentifier: "big") as! CategoryRow
        cell.section = indexPath.section
        cell.top = top
        cell.delegate = self
        cell.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(cameraTapped)))
        return cell
    } else {
        let cell = tableView.dequeueReusableCell(withIdentifier: "small") as! CategoryRow
        cell.section = indexPath.section
        cell.recent = recent
        cell.trending = trending
        cell.delegate = self
        return cell
    }
}

func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
    if section == 0 {
        return nil
    } else {
        let cell = self.tableView.dequeueReusableHeaderFooterView(withIdentifier: "MainHeader")
        let header = cell as! MainHeader
        if section == 1 {
            header.fillHeader("RECENT")
        } else if section == 2 {
            header.fillHeader("Trending + Now")
        } else {
            print("Unknown Section")
        }
        return header
    }
}

func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    if indexPath.section == 0 {
        return 300
    } else {
        return 100
    }
}

func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
    if section == 0 {
        return 0
    } else {
        return 50
    }
}

func tableView(_ tableView: UITableView, estimatedHeightForHeaderInSection section: Int) -> CGFloat {
    return 50
}
}

Answer 1

我意识到我需要做什么。我需要设置

ref.child("streams").observe

在对 Dispatch.Queue 的调用中。通过在调用 dispatch 之前设置引用，程序无法正确同步。应该是这样的：

DispatchQueue.main.async {
ref.child("streams").observe(.value, with: { (snapshot) in
        self.tableView.reloadSections(IndexSet(integer: 0), with: .automatic)
        self.tableView.reloadData()
    }
})

在开始直播后获取 UITableView 以刷新用户

Getting a UITableView to refresh users after one begins a live stream

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ios

swift

swift3