Swift 5 UITableViewController 来自 Json

Question

I'm new in swift 5. I have a trouble to call a function present in viewcontroller file:

func getJsonResultFromUrl (urlSrc: String, completion:@escaping (Arts)->()) {
    
    if let url = URL(string: urlSrc) {
        
        let task = URLSession.shared.dataTask(with: url) { (data, response, error) in
                 guard let data = data else { return }
                do {
                    var returnValue: Arts?
                    let decoder = JSONDecoder()
                    returnValue = try decoder.decode(Arts.self, from: data)
                    completion(returnValue!)
                } catch {
                    fatalError("Couldn't parse \(url) as \(Arts.self):\n\(error)")
                }
            }
            task.resume()
    }
}

from another file with class:

import UIKit

class ListStockArticle: UITableViewController {
    var datacell: (Arts) -> () = {_ in } // = 0
    var url: String = ""
    var nombreDeLigne: Int?
   

    init() {
       
        let urlPrefixLocal = "http://urlmasqued"
        let urlPrefixRemote = "http://urlmasqued"
        
        if self.url.validURL {
            
        } else {
          self.url = urlPrefixRemote + ajax
        }
        print(self.url)
        
       
        let k: () =  getJsonResultFromUrl(urlSrc: url, completion: (Arts) -> () ) 
        print(k)
////// -> I have error : Editor placeholder in source file

       /* getJsonResultFromUrl(urlSrc: self.url) { k in Arts()
      
          //  self.datacell = Arts
           self.nombreDeLigne = k.count
            
        }
*/
 
            super.init(nibName:nil, bundle:nil) // *
        }
        required init(coder aDecoder: NSCoder) {
            fatalError("init(coder:) has not been implemented")
        }


  
override  func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 20 //self.nombreDeLigne
}
    
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = UITableViewCell()
         cell.textLabel?.text = "Test"
         return cell
     }
    
}

The URL and get data from url works fine, but how can I call the function from another page? The idea is to get a list of product, and create a cell per products.

I will really appreciate help, this sounds strange for me. Regards

Answer 1

Try this: Singleton class

class SampleController {

private static var privateSharedInstance: SampleController?
static var sharedInstance: SampleController {
    if privateSharedInstance == nil {
        privateSharedInstance = SampleController()
    }
    return privateSharedInstance ?? SampleController()
}
private init() {
    
}

func getJsonResultFromUrl () {
    
}

}

Usage:

   override func viewDidLoad() {
    super.viewDidLoad()
    SampleController.sharedInstance.getJsonResultFromUrl()
}