i'm using web service to update components of uipickerview .
after appending all components to pickCityOptions array i call "reloadAllComponents" to update uipickerview.
i works great for updating components, but after updating all components still hidden till I tab on the picker , then all components appears.
@IBOutlet weak var pickCity: UIPickerView!
let defaults = NSUserDefaults.standardUserDefaults()
var pickCityOptions = [String]()
var items = [[String:String]()]
override func viewDidLoad() {
super.viewDidLoad()
self.pickCity.dataSource = self;
self.pickCity.delegate = self;
let urlPath = "http://www.waelmoharram.com/dalel/api/v1/cities"
let url = NSURL(string: urlPath)
let session = NSURLSession.sharedSession()
let task = session.dataTaskWithURL(url!, completionHandler: {data, response, error -> Void in
if error != nil {
print(error)
} else {
do {
let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options:NSJSONReadingOptions.MutableContainers ) as! NSArray
var item:AnyObject
for i in 0 ... jsonResult.count - 1 {
self.items.append([String:String]())
item = jsonResult[i]
self.items[i]["id"] = "\(item["id"]!)" as NSString as String
self.items[i]["city_name"] = item["city_name"] as! NSString as String
self.pickCityOptions.append(self.items[i]["city_name"]!)
}
self.pickCity.reloadAllComponents()
} catch {
print(error)
}
}
})
task.resume()
if let currentCityRow = self.defaults.stringForKey("city") {
self.pickCity.selectRow(Int(currentCityRow)!, inComponent: 0, animated: true)
}else{
self.pickCity.selectRow(0, inComponent: 0, animated: true)
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int)
{
defaults.setObject(row, forKey: "city")
}
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
return 1
}
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return pickCityOptions.count;
}
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
return pickCityOptions[row]
}
You need to use pickCityOptions as NSMutableArray.Don't use pickCityOptions.append instead use pickCityOptions.addObject
var pickCityOptions = NSMutableArray()
pickCityOptions.addObject(self.items[i]["city_name"]!)