Intercettare lo swipe su una UITableView in Swift

In questo articolo abbiamo visto come rempire una UITableView da JSON.

Poi abbiamo aggiunto anche un loading dialog, ma non è fondamentale per lo scopo di oggi.

Qui vediamo come intercettare lo swipe su una riga della UITableView, usando sempre Swift come linguaggio.

In pratica dobbiamo fare l'override di editActionsForRowAt.

Se siete partiti dagli articoli indicati, dobbiamo aggiungere questo blocco di codice:

    override func tableView(_ tableView: UITableView, editActionsForRowAt indexPath: IndexPath) -> [UITableViewRowAction]? {
        let current = self.tableArray[indexPath.row]
        
        let deleteTitle = NSLocalizedString("Cancella", comment: "Cancella action")
        let deleteAction = UITableViewRowAction(style: .destructive, title: deleteTitle) {
            (action, indexPath) in
            print(current.title)
        }
        
        let modificaTitle = NSLocalizedString("Modifica", comment: "Modifica action")
        let modificaAction = UITableViewRowAction(style: .normal, title: modificaTitle) {
            (action, indexPath) in
            print(current.title)
        }
//        modificaAction.backgroundColor = .green
        modificaAction.backgroundColor = UIColor(red:0.04, green:0.38, blue:0.13, alpha:1.0)
        
        return [modificaAction, deleteAction]
    }

Abbiamo aggiunto due azioni, che corrispondono a due pulsanti.

A click sul pulsante non facciamo altro che visualizzare il titolo in console; ovviamente dovete implementare le vostre azioni.

Qui sotto il codice completo:

import UIKit

struct Book {
    let title: String
    let author: String
    
    public init(title: String, author: String) {
        self.title = title
        self.author = author
    }
}

class ViewController: UITableViewController  {
    
    var tableArray = [Book] ()
    var loadingDialog = LoadingView()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        self.tableView.dataSource = self
        self.tableView.delegate = self
        
        getJson()
    }
    
    func getJson() {
        loadingDialog.showSpinner(onView: self.view)
        
        let url = URL(string: "https://www.mattepuffo.com/api/book/get.php")
        
        let task = URLSession.shared.dataTask(with: url!) {(data, response, error) in
            
            guard let jsonData = url else {
                return
            }
            
            guard let data = try? Data(contentsOf: jsonData) else { return }
            
            guard let json = try? JSONSerialization.jsonObject(with: data, options: []) else{ return }
            
            if let dictionary = json as? [String: Any] {
                
                guard let jsonArray = dictionary["books"] as? [[String: Any]] else {
                    return
                }
                
                for j in jsonArray {
                    guard let title = j["title"] as? String else { return }
                    guard let author = j["author"] as? String else { return }
                    self.tableArray.append(Book(title: title, author: author))
                }
                
            }
            
            DispatchQueue.main.async {
                self.tableView.reloadData()
                self.loadingDialog.removeSpinner()
            }
            
        }
        
        task.resume()
        
    }
    
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }
    
}

extension ViewController {
    
    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return self.tableArray.count
    }
    
    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        tableView.deselectRow(at: indexPath, animated: true)
    }
    
    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let current = self.tableArray[indexPath.row]
        let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as UITableViewCell
        cell.textLabel?.text = current.title
        cell.detailTextLabel?.text = "\(current.author)"
        return cell
    }
    
    override func tableView(_ tableView: UITableView, editActionsForRowAt indexPath: IndexPath) -> [UITableViewRowAction]? {
        let current = self.tableArray[indexPath.row]
        
        let deleteTitle = NSLocalizedString("Cancella", comment: "Cancella action")
        let deleteAction = UITableViewRowAction(style: .destructive, title: deleteTitle) {
            (action, indexPath) in
            print(current.title)
        }
        
        let modificaTitle = NSLocalizedString("Modifica", comment: "Modifica action")
        let modificaAction = UITableViewRowAction(style: .normal, title: modificaTitle) {
            (action, indexPath) in
            print(current.title)
        }
//        modificaAction.backgroundColor = .green
        modificaAction.backgroundColor = UIColor(red:0.04, green:0.38, blue:0.13, alpha:1.0)
        
        return [modificaAction, deleteAction]
    }
}

Enjoy!