TableView creates duplicates cells - swift

Question

when the like button is tapped it should increase the number of likes on the cell thats related to it but im having an issue which it creates a totally new cell with the updated number of likes I believe the problem is coming from how im loading my cells I believe I also need to add the function remove() so it clears the old data after the snapshot listener takes effect but im not too sure
func loaddailymotivation() {
FirebaseReferece(.MotivationDAILY).addSnapshotListener { querySnapshot, error in
guard let snapshot = querySnapshot else {
print("Error fetching snapshots: \(error!)")
return
}
snapshot.documentChanges.forEach { diff in
if (diff.type == .added) { // this line means if the chage that happened in the document was equal to added something
let data = diff.document.data()
print("we have\(snapshot.documents.count) documents in this array")
let dailyMotivationID = data["objectID"] as! String
let dailymotivationTitle = data["Motivation title"] as! String //calls the data thats heald inside of motivation title in firebase
let dailyMotivationScripture = data["daily motivation scripture"] as! String //calls the data thats heald inside of Motivation script in firebase
let dailyMotivationNumberOfLikes = data["Number of likes in daily motivation post"]as! Int
let MdataModel = motivationDailyModel(RealMotivationID: dailyMotivationID, RealmotivationTitle: dailymotivationTitle, RealmotivationScrip: dailyMotivationScripture, RealmotivationNumberOfLikes: dailyMotivationNumberOfLikes)
self.motivationThoughts.append(MdataModel)
}
//===== //=====
if (diff.type == .modified) {
print("Modified data: \(diff.document.data())")
let newdata = diff.document.data()
let dailyMotivationID = newdata["objectID"] as! String
let dailymotivationTitle = newdata["Motivation title"] as! String //calls the data thats heald inside of motivation title in firebase
let dailyMotivationScripture = newdata["daily motivation scripture"] as! String //calls the data thats heald inside of Motivation script in firebase
let dailyMotivationNumberOfLikes = newdata["Number of likes in daily motivation post"]as! Int
let MdataModel = motivationDailyModel(RealMotivationID: dailyMotivationID, RealmotivationTitle: dailymotivationTitle, RealmotivationScrip: dailyMotivationScripture, RealmotivationNumberOfLikes: dailyMotivationNumberOfLikes)
self.motivationThoughts.append(MdataModel)
// here you will receive if any change happens in your data add it to your array as you want
}
DispatchQueue.main.async {
self.tableview.reloadData()
}
}
}
}

Answer 1

Both branches do exactly the same.
In the modified branch you have to get the corresponding object in motivationThoughts, update it and put it back, rather than creating a new object.
Something like
if diff.type == .modified {
print("Modified data: \(diff.document.data())")
let newdata = diff.document.data()
let objectID = newdata["objectID"] as! String
guard let dailymotivationIndex = motivationThoughts.firstIndex(where: {$0.dailyMotivationID == objectID}) else { return }
var dailymotivation = self.motivationThoughts[dailymotivationIndex]
let dailyMotivationNumberOfLikes = newdata["Number of likes in daily motivation post"] as! Int
dailymotivation.RealmotivationNumberOfLikes = dailyMotivationNumberOfLikes
self.motivationThoughts[dailymotivationIndex] = dailymotivation
}
And I recommend to reload only the row in the modified branch rather than the entire table view.