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

Question

The landing page for an app I am working on has a place holder avatar named after the application that is present when no user is actively live streaming (using the Red5 Pro streaming framework for this).
However when someone does begin to stream, I want it to automatically refresh the tableview and display the new user's avatar. What I've written so far kind of works, but not entirely. When someone begins livestreaming the placeholder avatar does disappear, but the user that's streaming's avatar doesn't appear.
If I close the app and reopen it, then it is displayed correctly. Here's my code in Swift 3, what am I doing wrong? Should the call to refresh be moved out of ViewDidLoad? Am I using Dispatch Queue incorrectly? Thanks
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

I realized what I needed to do. I needed to set the
ref.child("streams").observe
in the call to Dispatch.Queue. By setting the reference before dispatch was called, the program wasn't syncing properly. It should be like this:
DispatchQueue.main.async {
ref.child("streams").observe(.value, with: { (snapshot) in
self.tableView.reloadSections(IndexSet(integer: 0), with: .automatic)
self.tableView.reloadData()
}
})