Loading JSON data into a table does not work

Question

Below is my code. The print (currency) function works here. This means that json data is being retrieved. But it does not appear in the table view.

class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource { 
@IBOutlet weak var tableView: UITableView! 
var TableData:Array< String > = Array < String >()

override func viewDidLoad()
{
   super.viewDidLoad()  
   get_data_from_url("http://api.fixer.io/latest")
}

Table part

public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return(TableData.count)
}

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

Retrieving JSON Data

func get_data_from_url(_ link:String)
{
    let url = URL(string: "http://api.fixer.io/latest")

    let task = URLSession.shared.dataTask(with: url!) { (data, response, error) in
        if error != nil
        {
            print ("ERROR")
        }
        else
        {
            if let content = data
            {
                do
                {
                    //Array
                    let myJson = try JSONSerialization.jsonObject(with: content, options: JSONSerialization.ReadingOptions.mutableContainers) as AnyObject

                    if let rates = myJson["rates"] as? NSDictionary
                    {
                        if let currency = rates["NOK"] as? String
                        {
                            print(currency)
                            self.TableData.append(currency)
                            self.tableView.reloadData()
                        }
                    }
                }
                catch
                {

                }
            }
        }
    }
    task.resume()


}

Data is displayed in xcode with print function. Therefore, it is clear that the data is retrieved. But the problem is loading the data into the table. Please help me download it.

Answer 1

Get data .. (your NOK is not String .. its Double)

let myJson = try JSONSerialization.jsonObject(with: content, options:[]) as [String:Any]

                if let rates = myJson["rates"] as? [String:Double],  
                   let currency = rates["NOK"] 
                {
                    print(currency)
                    self.tableData.append(String(currency))
                    DispatchQueue.main.async { 
                        self.tableView.reloadData() 
                    }
                }

---

// Declate array of String  
var tableData = [String]()

func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return tableData.count
}

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