CODEWITHSUNDEEP
iosuitableviewfirebase-realtime-databaseswift4
um app
um app

Reputation: 21

How to reload a tableView once a value has been appended to an array in swift 4.0

There I am having a problem reloading a tableView once a value has been appended to an array.

Here's my code

//
//  HomeViewController.swift
//  um
//
//  Created by Arnav on 17/09/18.
//  Copyright © 2018 Arnav. All rights reserved.
//

import UIKit
import Firebase
import FirebaseDatabase
import FirebaseAuth


class HomeTableViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {

    var questions = [Question]()

    override  func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
//       var postQuestion = Question(questionName: "Hi", created_by: "Bye")
//       print(postQuestion.name)
//       print(postQuestion.created)

        loadQuestions()

    }

    var list = ["milk", "bread"]

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

        return list.count

    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = UITableViewCell(style: UITableViewCellStyle.default, reuseIdentifier: "cell")
        cell.textLabel?.text = list[indexPath.row]

        return cell
    }


    func loadQuestions() {
        Database.database().reference().child("questionPosts").queryOrderedByKey().observe(.childAdded) { (snapshot) in
            if let dict = snapshot.value as? NSDictionary {
                //var questionName = dict["name"] as! String
                //var created_by = dict["email"] as! String
                let questionTitle = dict["name"] as? String ?? ""
                let created_by = dict["email"] as? String ?? ""

                self.list.append(questionTitle)
            }
        }
    }

This code is just added a new value to the list array and the table view displays whats from the list array but when I append something new to the list array and run it on the simulator the new value doesn't

Upvotes: 0

Views: 3147

Answers (5)

Flotery Extadives
Flotery Extadives

Reputation: 45

In my case, I remove all items in a previous array then reload in again.

I tried "didset" to reload anytime an array changed but no luck.

So, simply do

yourarray.removeall()

tableview.reloadData()

Upvotes: 0

Shruti
Shruti

Reputation: 1849

You need to create an outlet for your tableview and once your data is loaded you can call

tableview.reloadData()

Alternatively, you can cell the above function on the didSet of your array like below:

var questions = [Question]() {
    didSet {
        // because we perform this operation on the main thread, it is safe
        DispatchQueue.main.async {
            self?.tableView.reloadData()
        }
    }

didSet will be called every time you change something in your questions array

Upvotes: 1

Farid Rahmani
Farid Rahmani

Reputation: 113

After adding the new element to the list, call insertRowAtIndexPaths:withRowAnimation on your tableView as follows:

self.list.append(questionTitle)
let indexPath = IndexPath(row:self.list.count - 1, section:0)
tableView.insertRowsAtIndexPaths([indexPath], withRowAnimation:.default)

Upvotes: 2

Jorge Costa
Jorge Costa

Reputation: 307

You can use the property observer didSet. 

var questions = [Question]() {
    didSet {
        Dispatch.main.async {
            self.tableView.reloadData()
        }
    }
}

For more information click here.

Upvotes: 2

user10079585
user10079585

Reputation: 

import UIKit
import Firebase
import FirebaseDatabase
import FirebaseAuth



class HomeTableViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {



    var questions = [Question]()

    override  func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
//       var postQuestion = Question(questionName: "Hi", created_by: "Bye")
//       print(postQuestion.name)
//       print(postQuestion.created)

        loadQuestions()
        yourtableView.reloadData()

    }






    var list = ["milk", "bread"]




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


        return list.count

    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = UITableViewCell(style: UITableViewCellStyle.default, reuseIdentifier: "cell")
        cell.textLabel?.text = list[indexPath.row]

        return cell
    }


    func loadQuestions() {
        Database.database().reference().child("questionPosts").queryOrderedByKey().observe(.childAdded) { (snapshot) in
            if let dict = snapshot.value as? NSDictionary {
                //var questionName = dict["name"] as! String
                //var created_by = dict["email"] as! String
                let questionTitle = dict["name"] as? String ?? ""
                let created_by = dict["email"] as? String ?? ""

                self.list.append(questionTitle) 




            }
        }
    }

Upvotes: 0

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