我试图在 Swift 中更新数据后重新加载表视图,但它似乎不起作用。当我更改选项卡并返回时,表视图会重新加载,但不会自动加载。
这是我的代码:
override func viewDidLoad() {
super.viewDidLoad()
// some code
refresh(self)
}
func refresh(sender: AnyObject) {
// Reload the data
self.tableView.reloadData()
}
我不明白为什么它在 Objective-C 中有效但在 Swift 中不起作用......
我还尝试添加:
dispatch_async(dispatch_get_main_queue(), { () -> Void in
self.tableView.reloadData()
})
因为我在其他帖子中看到了这个,但它也不起作用。
感谢您的帮助
编辑:我的整个视图控制器
class HighwaysViewController: UITableViewController {
var highways: [Highway]!
override func viewDidLoad() {
super.viewDidLoad()
// Uncomment the following line to preserve selection between presentations
// self.clearsSelectionOnViewWillAppear = false
// Uncomment the following line to display an Edit button in the navigation bar for this view controller.
// self.navigationItem.rightBarButtonItem = self.editButtonItem()
highways = [Highway]()
// On ajoute le "Pull to refresh"
refreshControl = UIRefreshControl()
refreshControl!.addTarget(self, action: Selector("refresh:"), forControlEvents: UIControlEvents.ValueChanged)
tableView.addSubview(refreshControl!)
refresh(self)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func refresh(sender: AnyObject) {
// Afficher l'icône de chargement dans la barre de status
UIApplication.sharedApplication().networkActivityIndicatorVisible = true
// On télécharge les autoroutes
var url = NSURL(string: "http://theurl.com")! // URL du JSON
var request = NSURLRequest(URL: url) // Création de la requête HTTP
var queue = NSOperationQueue() // Création de NSOperationQueue à laquelle le bloc du gestionnaire est distribué lorsque la demande complète ou échoué
// Envoi de la requête asynchrone en utilisant NSURLConnection
NSURLConnection.sendAsynchronousRequest(request, queue: queue, completionHandler:{(response: NSURLResponse!, data: NSData!, error: NSError!) ->Void in
// Gestion des erreurs de connexion
if error != nil {
// Masquer l'icône de chargement dans la barre de status
UIApplication.sharedApplication().networkActivityIndicatorVisible = false
println(error.localizedDescription)
let errorAlert = UIAlertView(title: "Erreur", message: error.localizedDescription, delegate: self, cancelButtonTitle: "OK")
errorAlert.show()
}
else {
// Récupération du JSON et gestion des erreurs
let json = JSON(data: data)
if let highwaysData = json.arrayValue {
for highway in highwaysData {
var newHighway = Highway(ids: highway["Ids"].stringValue, name: highway["Name"].stringValue, label: highway["Direction"].stringValue, length: highway["Length"].stringValue, directions: highway["Direction"].stringValue, operateur: highway["Operator"].stringValue)
self.highways.append(newHighway)
}
}
}
})
if (self.refreshControl!.refreshing) {
self.refreshControl!.endRefreshing()
}
tableView.reloadData() // Here is the problem
// Masquer l'icône de chargement dans la barre de status
UIApplication.sharedApplication().networkActivityIndicatorVisible = false
}
// MARK: - Table view data source
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// Return the number of rows in the section.
return highways.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("highwayCell", forIndexPath: indexPath) as UITableViewCell
// Configure the cell...
let tableCell = highways[indexPath.row]
let nameLabel = cell.viewWithTag(1) as UILabel
let directionLabel = cell.viewWithTag(2) as UILabel
nameLabel.text = tableCell.name!
directionLabel.text = tableCell.getDirections()
return cell
}
/*
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using [segue destinationViewController].
// Pass the selected object to the new view controller.
}
*/
}