My app displays the price of something in £ currency by default when opening the app. I can change the currency but when the app is closed it reverts back to £. How can I make the user selection on the picker override the default currency and save until changed again? I think it is using UserDefaults? I haven't been able to figure it out yet.
class ViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource {
// let defaults = UserDefaults.standard
let baseURL = "https://apiv2.bitcoinaverage.com/indices/global/ticker/BTC" // API
let currencyArray = ["AUD", "BRL","CAD","CNY","EUR","GBP","HKD","IDR","ILS","INR","JPY","MXN","NOK","NZD","PLN","RON","RUB","SEK","SGD","USD","ZAR"] // List of currencies
let currencySymbolArray = ["$", "R$", "$", "¥", "€", "£", "$", "Rp", "₪", "₹", "¥", "$", "kr", "$", "zł", "lei", "₽", "kr", "$", "$", "R"] // Currency symbols
var currencySelected = ""
var finalURL = ""
// Pre-setup IBOutlets
@IBOutlet weak var priceLabel: UILabel!
@IBOutlet weak var currencyPicker: UIPickerView!
@IBOutlet weak var doneButton: UIButton!
@IBAction func doneButton(_ sender: UIButton) {
currencyPicker.isHidden = true
doneButton.isHidden = true
}
override func viewDidLoad() {
super.viewDidLoad()
currencyPicker.delegate = self
currencyPicker.dataSource = self
currencyPicker.selectRow(5, inComponent:0, animated:false) // Select default currency choice to £
// Print out the default row price
finalURL = baseURL + currencyArray[5]
print(finalURL)
currencySelected = currencySymbolArray[5]
getBitcoinData(url: finalURL)
currencyPicker.isHidden = true
doneButton.isHidden = true
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(self.handleTap(_:)))
tapGesture.numberOfTapsRequired = 1
priceLabel.isUserInteractionEnabled = true
priceLabel.addGestureRecognizer(tapGesture)
}
@objc func handleTap(_ sender: UITapGestureRecognizer? = nil)
{
self.currencyPicker.isHidden = false
self.doneButton.isHidden = false
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
// Number of columns
func numberOfComponents(in pickerView: UIPickerView) -> Int {
return 1
}
// Number of rows
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return currencyArray.count // Number of rows = the amount in currency array
}
// Row Title
func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
return currencyArray[row]
}
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
finalURL = baseURL + currencyArray[row]
print(finalURL)
currencySelected = currencySymbolArray[row]
getBitcoinData(url: finalURL)
}
//MARK: - Networking
/***************************************************************/
func getBitcoinData(url: String) {
Alamofire.request(url, method: .get)
.responseJSON { response in
if response.result.isSuccess {
print("Sucess! Got the Bitcoin data.")
let bitcoinJSON : JSON = JSON(response.result.value!)
self.updateBitcoinData(json: bitcoinJSON)
} else {
print("Error: \(String(describing: response.result.error))")
self.priceLabel.text = "Error: Check Connection"
}
}
}
//MARK: - JSON Parsing
/***************************************************************/
func updateBitcoinData(json : JSON) {
if let bitcoinResult = json["ask"].double {
priceLabel.text = currencySelected + String(bitcoinResult)
} else {
priceLabel.text = "Price Unavaiable"
}
}
// let timer = Timer.scheduledTimer(timeInterval: 15, target: self, selector: #selector(self.someMethod), userInfo: nil, repeats: true)
}
In viewDidLoad()
if let selectedCurrency = UserDefaults.standard.integer(forKey: "selectedCurrency") {
currencyPicker.selectRow(selectedCurrency, inComponent:0, animated:false)
}
else {
currencyPicker.selectRow(5, inComponent:0, animated:false)
}
In didSelectRow
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
UserDefaults.standard.set(row, forKey: "selectedCurrency")
}