Chat messages does not update properly - ios

Question

This is the full code for the chatViewController. Every time when I click send button, the text messages will have some duplicate and fly out of text box as shown in this picture.
However, when I exit the chat and re-enters,those message that fly out of the box are gone. It is not because of duplicated messages in Array, I believe it should be due to either Cache issue or the updating mechanism is wrong.
Every time when I close chat and re-enter, the fly out of text box chat does not exist, everything is fine. If I do not click on send Message,the Messages all reload fine.
It is only when I click send message, there will be a few (not all) messages that duplicate and fly out of box. When I exit the chat, and re-enter,the out of box chat will be gone and everything is normal.
I consulted with other programmers who saw my code and said it is most likely because when you click send button, it fetches complete dataset, and when it display on your screen, the old data on your screen (even though you have removed them from your array) messed up with the new data. I asked them how to solve it, they are not sure because they are Android developers.
A train of thought I was thinking: cache the old messages, add the new messages but make sure they do not conflict with the old messages in the cache?
import UIKit
import Firebase
import FirebaseStorage
import FirebaseDatabase
import FirebaseFirestore
import CoreData
class ChatViewController: UIViewController, UICollectionViewDelegate, UICollectionViewDataSource {
#IBOutlet weak var collectionView: UICollectionView!
#IBOutlet weak var messageText: UITextField!
#IBAction func back(_ sender: Any) {
back()
}
#IBOutlet weak var profileImage: UIImageView!
#IBOutlet weak var usernameLabel: UILabel!
#IBAction func sendTextMessage(_ sender: Any) {
chats.removeAll()
self.sendDataToDatabase(message: messageText.text!)
messageText.text = nil
self.loadPosts()
self.loadPostsReceivedMessage()
delayCompletionHandler {
self.collectionView.reloadData()
}
}
let cellIdentifier = "chatNow"
var chats = [Chat]()
var posts = [Post]()
var receiverIDNumber = ""
var profileImageUrl = ""
var senderString = ""
var conversationsCounterInt = 0
var timestamp = String(Int(Date().timeIntervalSince1970))
let db = Firestore.firestore()
override func viewDidLoad() {
super.viewDidLoad()
let yourNibName = UINib(nibName: "ChatCollectionViewCell", bundle: nil)
collectionView.register(yourNibName, forCellWithReuseIdentifier: cellIdentifier)
self.collectionView.dataSource = self
self.collectionView.delegate = self
print(receiverIDNumber)
usernameLabel.text! = receiverIDNumber
setUpProfile()
set()
print("is there anything"+profileImageUrl)
//Making circular profile picture
profileImage.layer.borderWidth = 1.0
profileImage.layer.masksToBounds = false
profileImage.layer.borderColor = UIColor.white.cgColor
profileImage.layer.cornerRadius = profileImage.frame.size.width / 2
profileImage.clipsToBounds = true
print("waka"+senderString)
self.loadPosts()
self.loadPostsReceivedMessage()
delayCompletionHandler {
self.collectionView.reloadData()
}
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
navigationItem.title = "Chat"
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func back() {
let storyboard = UIStoryboard(name: "Main" , bundle: nil)
let tabViewController = storyboard.instantiateViewController(withIdentifier: "tab")
present(tabViewController, animated: true,completion: nil)
}
func set() {
let uid = Auth.auth().currentUser?.uid
let ref = Database.database().reference()
ref.child("users").child(uid!).observeSingleEvent(of: .value, with: { (snapshot) in
if let dic = snapshot.value as? [String: AnyObject] {
self.senderString = dic["username"] as! String
print("this"+self.senderString)
}
})
}
func sendDataToDatabase(message: String){
let ref = Database.database().reference()
let senderIDNumber = Auth.auth().currentUser?.uid
let timeStampString = String(Int(Date().timeIntervalSince1970))
db.collection("chats").addDocument(data: ["message": messageText.text!, "senderID": senderIDNumber!,"receiverID": receiverIDNumber,"timestamp": timeStampString,"profileUrl": profileImageUrl, "sender": self.senderString])
{ err in
if let err = err {
print("Error writing document: \(err)")
} else {
print("Document successfully written!")
}
}
}
func logout(){
let storyboard = UIStoryboard(name: "Main" , bundle: nil)
let loginViewController = storyboard.instantiateViewController(withIdentifier: "login")
present(loginViewController, animated: true,completion: nil)
}
func delayCompletionHandler(completion:#escaping (() -> ())) {
let delayInSeconds = 0.3
DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + delayInSeconds) {
completion()
}
}
func numberOfSections(in collectionView: UICollectionView) -> Int {
return 1
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int{
return chats.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell{
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellIdentifier, for: indexPath) as! ChatCollectionViewCell
let senderIDNumber = Auth.auth().currentUser?.uid
//Setup the messageReceived and messageSent
if chats[indexPath.row].senderID == senderIDNumber {
if let chatsText = chats[indexPath.row].message{
let size = CGSize(width: 250, height: 1000)
let options = NSStringDrawingOptions.usesFontLeading.union(.usesLineFragmentOrigin)
let estimatedFrame = NSString(string: chatsText).boundingRect(with: size, options: options, attributes: [NSAttributedStringKey.font : UIFont.systemFont(ofSize: 18)], context: nil)
cell.messageSend.frame = CGRect(x:8,y:0,width:estimatedFrame.width + 16, height:estimatedFrame.height + 20)
cell.textBubbleView.frame = CGRect(x:0,y:0,width:estimatedFrame.width + 16 + 8, height:estimatedFrame.height + 20)
//showOutgoingMessage(text: chats[indexPath.row].message)
cell.messageSend.text = chats[indexPath.row].message
}
}
else {
cell.messageReceived.text = chats[indexPath.row].message
let chatsText = chats[indexPath.row].message
let size = CGSize(width: 250, height: 1000)
let options = NSStringDrawingOptions.usesFontLeading.union(.usesLineFragmentOrigin)
let estimatedFrame = NSString(string: chatsText!).boundingRect(with: size, options: options, attributes: [NSAttributedStringKey.font : UIFont.systemFont(ofSize: 18)], context: nil)
cell.messageReceived.frame = CGRect(x:view.frame.width - estimatedFrame.width - 30,y:0,width:estimatedFrame.width + 16, height:estimatedFrame.height + 20)
cell.textBubbleView.frame = CGRect(x:view.frame.width - estimatedFrame.width - 30,y:0,width:estimatedFrame.width + 16 + 4, height:estimatedFrame.height + 20)
}
return cell
}
func collectionView(_ collectionView: UICollectionView,
layout collectionViewLayout: UICollectionViewLayout,
sizeForItemAt indexPath: IndexPath) -> CGSize {
if let chatsText = chats[indexPath.row].message {
let size = CGSize(width: 250, height: 1000)
let options = NSStringDrawingOptions.usesFontLeading.union(.usesLineFragmentOrigin)
let estimatedFrame = NSString(string: chatsText).boundingRect(with: size, options: options, attributes: [NSAttributedStringKey.font : UIFont.systemFont(ofSize: 18)], context: nil)
return CGSize(width: view.frame.width, height: estimatedFrame.height + 20)
}
return CGSize(width: view.frame.width, height: 200)
}
//Get Message sent
func loadPosts() {
let senderIDNumber = Auth.auth().currentUser?.uid
let chatsRef = db.collection ("chats").order (by: "timestamp", descending: false)
let sentListener = chatsRef.whereField ("senderID", isEqualTo: senderIDNumber!)
.whereField ("receiverID", isEqualTo: receiverIDNumber)
.addSnapshotListener() {
querySnapshot,
error in
guard let documentChanges = querySnapshot?.documentChanges else {
print ("Error fetching documents: \(error!)")
return
}
for documentChange in documentChanges {
if (documentChange.type == .added) {
let data = documentChange.document.data ()
print("Message send: \(data)")
let messageText = data["message"] as? String
let senderIDNumber = data["senderID"] as? String
let receiverIDNumber = data["receiverID"] as? String
let timestamp = data["timestamp"] as? String
guard let sender = data["sender"] as? String else {return}
// let conversationsCounter = document.data()["conversationsCounter"] as? Int
guard let profileUrl = data["profileUrl"] as? String else { return}
let chat = Chat(messageTextString: messageText!, senderIDNumber: senderIDNumber!, receiverIDNumber: receiverIDNumber!, timeStampString: timestamp!, profileImageUrl: profileUrl, senderString: sender)
self.chats.append(chat)
print(self.chats)
}
}
}
}
//Get message received
func loadPostsReceivedMessage() {
let chatsRef = db.collection("chats").order(by: "timestamp", descending: false)
print("thecurrentreceiver"+senderString)
print("thecurrentsender"+receiverIDNumber)
let receivedListener = chatsRef.whereField("receiverID", isEqualTo: senderString).whereField("sender", isEqualTo: receiverIDNumber)
.addSnapshotListener() {
querySnapshot,
error in
guard let documentChanges = querySnapshot?.documentChanges else {
print ("Error fetching documents: \(error!)")
return
}
for documentChange in documentChanges {
if (documentChange.type == .added) {
let data = documentChange.document.data ()
print("Message received: \(data)")
let messageText = data["message"] as? String
let senderIDNumber = data["senderID"] as? String
let receiverIDNumber = data["receiverID"] as? String
let timestamp = data["timestamp"] as? String
guard let sender = data["sender"] as? String else {return}
// let conversationsCounter = document.data()["conversationsCounter"] as? Int
guard let profileUrl = data["profileUrl"] as? String else { return}
let chat = Chat(messageTextString: messageText!, senderIDNumber: senderIDNumber!, receiverIDNumber: receiverIDNumber!, timeStampString: timestamp!, profileImageUrl: profileUrl, senderString: sender)
self.chats.append(chat)
print(self.chats)
self.chats.sort{$0.timestamp < $1.timestamp}
}
}
}
}
func setUpProfile() {
guard let url = URL(string: profileImageUrl) else { return}
let task = URLSession.shared.dataTask(with: url){ data, reponse, error in
if error != nil {
print(error!)
} else{
DispatchQueue.main.async(execute: {
self.profileImage.image = UIImage(data: data!)
})
}
}
task.resume()
}
}