Connecting JSON from external server to Swift tableView - ios

Question

I am new to Swift, and am trying to create a table that reads JSON data from my website. I followed some tutorials, and was able to get my code to work with a table controller. Now I'm trying to use a view controller with a table view inside, so I can have more customization. My problem is, I can't get the data to actually show up when I try to use my new code.
This is what I have in my viewController.swift:
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var tableView: UITableView!
var TableData:Array< String > = Array < String >()
override func viewDidLoad() {
super.viewDidLoad()
get_data_from_url("http://www.stevenbunting.org/Alliris/service.php")
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return TableData.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
cell.textLabel?.text = TableData[indexPath.row]
return cell
}
func get_data_from_url(_ link:String)
{
let url:URL = URL(string: link)!
let session = URLSession.shared
let request = NSMutableURLRequest(url: url)
request.httpMethod = "GET"
request.cachePolicy = NSURLRequest.CachePolicy.reloadIgnoringCacheData
let task = session.dataTask(with: request as URLRequest, completionHandler: {
(
data, response, error) in
guard let _:Data = data, let _:URLResponse = response , error == nil else {
return
}
self.extract_json(data!)
})
task.resume()
}
func extract_json(_ data: Data)
{
let json: Any?
do
{
json = try JSONSerialization.jsonObject(with: data, options: [])
}
catch
{
return
}
guard let data_list = json as? NSArray else
{
return
}
if let countries_list = json as? NSArray
{
for i in 0 ..< data_list.count
{
if let country_obj = countries_list[i] as? NSDictionary
{
if let country_name = country_obj["user"] as? String
{
if let country_code = country_obj["friendlist"] as? String
{
TableData.append(country_name + " [" + country_code + "]")
}
}
}
}
}
DispatchQueue.main.async(execute: {self.do_table_refresh()
})
}
func do_table_refresh()
{
self.tableView.reloadData()
}
}

Answer 1

Probably you didn't set the tableView's dataSource. To do this, implement the UITableViewDataSource-protocol in the ViewController-class and set the tableView's dataSource-property to self in the viewDidLoad(), for example:
class ViewController: UIViewController, UITableViewDataSource {
// ...
override func viewDidLoad() {
super.viewDidLoad()
tableView.dataSource = self
// ...
}
//...
}
Oh, and don't forget about the Apple Transport Security-settings, otherwise you won't see anything as iOS doesn't allow HTTP anymore, you have use HTTPS. The right way to handle this is to get an SSL-Certificate for your domain.
The quick'n'dirty and absolutely not recommended way is to disable ATS or to set an exception for certain, trustworthy domains.