Change textfield dynamically and label to currency

Question

New to swift, I built a simple app with a texfield, a button and a label. I want to be able to enter a number into the textfield and have it dynamically change to a currency, i.e. 1200 changes to $1,200.00. Then when I push my button I want to have that currency multiply with a constant say 2 and display the currency amount in the label as it did in the textfield. I can't seem to get this currency converter to work in Swift 3. My code is pretty simplistic so I have not really showed anything here just looking for a way to format the textfield and label answer.

import UIKit

class ViewController: UIViewController,  UIPickerViewDelegate, UIPickerViewDataSource, UITextFieldDelegate {

@IBOutlet var Picker1: UIPickerView!
 var Array = ["1", "2"]

@IBOutlet var grossSalary: UITextField!

@IBOutlet var text: UILabel!

var mult = 2


override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
    Picker1.delegate = self
    Picker1.dataSource = self
     grossSalary.delegate = self
     grossSalary.keyboardType = UIKeyboardType.numbersAndPunctuation
    text.text = ""

}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    return Array[row]
}

func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
    return Array.count
}

func numberOfComponents(in pickerView: UIPickerView) -> Int{
    return 1
}



@objc(textField:shouldChangeCharactersInRange:replacementString:) func textField(_ grossSalary: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
    let invalidCharacters = CharacterSet(charactersIn: "0123456789.").inverted
    return string.rangeOfCharacter(from: invalidCharacters, options: [], range: string.startIndex ..< string.endIndex) == nil
}

func textFieldShouldReturn(_ textField: UITextField) -> Bool {
    grossSalary.resignFirstResponder()
    return true
}

@IBAction func changetext(_ sender: AnyObject) {
   text.text = grossSalary.text
  //  let result = (text.text.toInt() ?? 0) * 2
  //  text.text = "\(result)"

    let a = grossSalary.text
    let b = Int(a!)! * mult

    text.text = ("$\(b)0")



}

}

Please update your question with your relevant code so people can help you fix it. — rmaddy, Oct 29 '16 at 05:40
Possible duplicate of [Struggling with NSNumberFormatter in Swift for currency](http://stackoverflow.com/questions/24960621/struggling-with-nsnumberformatter-in-swift-for-currency) — Lawrence413, Oct 29 '16 at 08:14
I want the textField to dynamically change when a number is entered and have the result show in the label as a currency number. — William Lloyd, Oct 29 '16 at 18:12
I have all the answers; will post soon so that others may benefit from the knowledge I have acquired. — William Lloyd, Nov 09 '16 at 21:51
Please don't deface your question. If it is no longer relevant, you can always delete it if you want - or better, post your own *answer* to your issue. Thanks. — Eric Aya, Nov 10 '16 at 10:22

score 1 · Accepted Answer · edited Nov 15 '17 at 13:15

Used Number Formatter() to achieve result.

//dynamically change to currency formatted text for cash down payment
func myTextFieldDidChange1(_ textField: UITextField) {

    if let amountString1 = cdptext.text?.currencyInputFormatting() {
         cdptext.text = amountString1
    }
}

extension String {

// formatting text for currency textField
func currencyInputFormatting() -> String {

    var number: NSNumber!
    let formatter = NumberFormatter()
    formatter.numberStyle = .currencyAccounting
    formatter.currencySymbol = "$"
    formatter.maximumFractionDigits = 2
    formatter.minimumFractionDigits = 2

    var amountWithPrefix = self

    // remove from String: "$", ".", ","
    let regex = try! NSRegularExpression(pattern: "[^0-9]", options: .caseInsensitive)
    amountWithPrefix = regex.stringByReplacingMatches(in: amountWithPrefix, options: NSRegularExpression.MatchingOptions(rawValue: 0), range: NSMakeRange(0, self.characters.count), withTemplate: "")

    let double = (amountWithPrefix as NSString).doubleValue
    number = NSNumber(value: (double / 100))

    // if first number is 0 or all numbers were deleted
    guard number != 0 as NSNumber else {
        return ""
    }

    return formatter.string(from: number)!
  }
}

score 0 · Answer 2 · answered Aug 24 '17 at 02:59

You can use this:

let balance = 125.78

let balanceCurrency = balance.currency

lblBalance.text = balanceCurrency

This return $0.00

extension NumberFormatter {
    convenience init(style: Style) {
        self.init()
        numberStyle = style
    }
}

extension Formatter {

    static let currency = NumberFormatter(style: .currency)

}

extension FloatingPoint {

    var currency: String {
        return Formatter.currency.string(for: self) ?? ""
    }

}

Change textfield dynamically and label to currency

2 Answers2