API to table view, Add columns and refresh - swift

Question

Attaching the code here.
This is the API: " https://bittrex.com/api/v1.1/public/getmarketsummaries "
I am wanting to add the "High" and "Low" in columns beside "MarketName"
Also, I want to refresh this every 10 seconds.
The refresh part, I am getting error, for sendUpdateRequest().
The full code is:
import UIKit
var listData = [[String : AnyObject]]()
class DemoJsonTableViewController: UITableViewController {
var listData = [[String : AnyObject]]()
override func viewDidLoad() {
super.viewDidLoad()
var timer : Timer? = nil
timer = Timer.scheduledTimer(timeInterval: 10, target: self, selector: (#selector(self.sendUpdateRequest)), userInfo: nil, repeats: true)
func sendUpdateRequest(){
let url:String = "https://bittrex.com/api/v1.1/public/getmarketsummaries"
let urlRequest = URL(string: url)
URLSession.shared.dataTask(with: urlRequest!) { (data, response, error) in
if(error != nil){
print(error.debugDescription)
}
else{
do{
var response = try JSONSerialization.jsonObject(with: data!, options: .allowFragments) as! [String:AnyObject]
self.listData = response["result"] as! [[String:AnyObject]]
DispatchQueue.main.async {
self.tableView.reloadData()
}
}catch let error as NSError{
print(error)
}
}
}.resume()
}
}
// MARK: - Table view data source
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.listData.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
let item = self.listData[indexPath.row]
cell.textLabel?.text = item["MarketName"] as? String
let lastValue = item["Last"] as? NSNumber
cell.detailTextLabel?.text = lastValue?.stringValue
print(self.listData.count)
return cell
}

Answer 1

This is what you need. Copy paste the entire code.
import UIKit
class DemoJsonTableViewController: UITableViewController {
var listData = [[String : AnyObject]]()
override func viewDidLoad() {
super.viewDidLoad()
tableView.register(DrawerCell.self, forCellReuseIdentifier: "Cell")
self.sendUpdateRequest()
Timer.scheduledTimer(timeInterval: 10, target: self, selector: (#selector(self.sendUpdateRequest)), userInfo: nil, repeats: true)
}
func sendUpdateRequest(){
let url:String = "https://bittrex.com/api/v1.1/public/getmarketsummaries"
let urlRequest = URL(string: url)
URLSession.shared.dataTask(with: urlRequest!) { (data, response, error) in
if(error != nil){
print(error.debugDescription)
}
else{
do{
var response = try JSONSerialization.jsonObject(with: data!, options: .allowFragments) as! [String:AnyObject]
self.listData = response["result"] as! [[String:AnyObject]]
DispatchQueue.main.async {
self.tableView.reloadData()
}
}catch let error as NSError{
print(error)
}
}
}.resume()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
// MARK: - Table view data source
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.listData.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! DrawerCell
let item = self.listData[indexPath.row]
cell.TitleLabel.text = item["MarketName"] as? String
cell.Description.text = String(describing: item["Last"] as? NSNumber)
cell.HighLabel.text = String(describing: item["High"] as! NSNumber)
cell.LowLabel.text = String(describing: item["Low"] as! NSNumber)
return cell
}
}
class DrawerCell: UITableViewCell {
var TitleLabel: UILabel = UILabel()
var Description: UILabel = UILabel()
var HighLabel: UILabel = UILabel()
var LowLabel: UILabel = UILabel()
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
TitleLabel.textColor = UIColor.black
TitleLabel.font = UIFont.init(name: "AppleSDGothicNeo-Bold", size: 10)
TitleLabel.textAlignment = .left
contentView.addSubview(TitleLabel)
Description.textColor = UIColor.black
Description.font = UIFont.init(name: "AppleSDGothicNeo-Bold", size: 8)
Description.textAlignment = .left
contentView.addSubview(Description)
HighLabel.textColor = UIColor.black
HighLabel.font = UIFont.init(name: "AppleSDGothicNeo-Bold", size: 10)
HighLabel.textAlignment = .center
contentView.addSubview(HighLabel)
LowLabel.textColor = UIColor.black
LowLabel.font = UIFont.init(name: "AppleSDGothicNeo-Bold", size: 10)
LowLabel.textAlignment = .center
contentView.addSubview(LowLabel)
}
override func layoutSubviews() {
super.layoutSubviews()
TitleLabel.frame = CGRect(x: 10, y: 0, width: self.frame.size.width - 110, height: 20)
Description.frame = CGRect(x: 10, y: 20, width: self.frame.size.width - 110, height: 20)
HighLabel.frame = CGRect(x: self.frame.size.width - 110, y: 0, width: 100, height: 20)
LowLabel.frame = CGRect(x: self.frame.size.width - 110, y: 20, width: 100, height: 20)
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override public func prepareForReuse() {
TitleLabel.text = nil
Description.text = nil
HighLabel.text = nil
LowLabel.text = nil
}
}

Answer 2

Couple of issues with the code here:
Firstly, you are defining sendUpdateRequest() inside viewDidLoad(). Move the whole function outside these enclosing braces to get rid of that error. Second, you don't need to define listData outside the class.
You can then use your existing code for the refresh functionality.
For the columns for High And Low, you will need to subclass a UITableViewCell and add extra labels.
Follow the steps outlined here: How to add more than two labels to prototype cell?.