Рассчитать промежуточный итог с использованием кортежей и 3 UIPickerviews

Question

Я новичок в программировании Swift. Я создал 3 сборщика и добавил некоторые значения из кортежей. Моя задача заключается в том, что я не знаю, как отделить двойники от кортежей и рассчитать промежуточный итог с количеством. Какой бы тип билета отображался на Picker2, мне нужно умножить его на количество от Picker3 и отобразить промежуточный итог.

Вот мое кодирование.

import UIKit 

class BuyTicketViewController: UIViewController, UIPickerViewDelegate,UIPickerViewDataSource, UITextFieldDelegate{ 
    @IBOutlet weak var Picker1: UIPickerView! = UIPickerView() 
    @IBOutlet weak var Picker2: UIPickerView! = UIPickerView() 
    @IBOutlet weak var Picker3: UIPickerView! = UIPickerView() 
    @IBOutlet weak var cityTextField: UITextField! 
    @IBOutlet weak var typeTextField: UITextField! 
    @IBOutlet weak var qtyTextField: UITextField! 

    var seletedItemArray = [(String,Double)]() 
    var Cities = ["Las Vegas","Los Angeles","New York"] 
    var typeLasVegas = [("City Tour $20.50", 20.50),("Museum $10.00", 10.00), ("Amusement Park $75.00",75.00)] 
    var typeLosAnglese = [("City Tour $29.99", 29.99),("Museum $15.00", 15.00), ("Amusement Park $79.99",79.99)] 
    var typeNewYork = [("City Tour $39.99", 39.99),("Museum $12.50", 12.50), ("Amusement Park $65.00",65.00)] 

    var Qt = [("1", 1.0),("2", 2.0),("3",3.0),("4", 4.0),("5",5.0),("6",6.0)] 

    var subTotal = 0.0 
    var ticketQty = 0 
    var ticketPrice = 0.0 

    override func viewDidLoad() { 
     super.viewDidLoad() 

     Picker1.isHidden = true 
     Picker2.isHidden = true 
     Picker3.isHidden = true 

     cityTextField.delegate = self 
     Picker1.delegate = self 
     typeTextField.delegate = self 
     Picker2.delegate = self 
     qtyTextField.delegate = self 
     Picker3.delegate = self 

     self.cityTextField.inputView = self.Picker1 
     self.typeTextField.inputView = self.Picker2 
     self.qtyTextField.inputView = self.Picker3 

     Picker1.tag = 0 
     Picker2.tag = 1 
     Picker3.tag = 2 
     // Do any additional setup after loading the view. 
    } 

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

    func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? { 
     if pickerView.tag == 0 
     { 
      return Cities[row] 
     } 
     else if pickerView.tag == 1 
     { 
      return seletedItemArray[row].0 
     } 
     else if pickerView.tag == 2 
     { 
      return Qt[row].0 
     } 
     return "" 
    } 

    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int { 
     if pickerView.tag == 0 
     { 
      return Cities.count 
     } 
     else if pickerView.tag == 1 
     { 
      return seletedItemArray.count 
     } 
     else if pickerView.tag == 2 
     { 
      return Qt.count 
     } 
     return 1 
    } 

    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) 
    { 
     if pickerView.tag == 0 
     { 
      switch row { 
      case 0: 
       seletedItemArray = typeLasVegas 
      case 1: 
       seletedItemArray = typeLosAnglese 
      case 2: 
       seletedItemArray = typeNewYork 

      default: 
       seletedItemArray = [] 
      } 
      Picker2.reloadAllComponents() 
      cityTextField.text = Cities[row] 
      Picker1.isHidden = true 
      Picker2.isHidden = false 
     } 
     else if pickerView.tag == 1 
     { 
      let item = seletedItemArray[row].0 

      if seletedItemArray[row] == typeLasVegas[row] 
      { 
       typeTextField.text = item 

      } else if seletedItemArray[row] == typeLosAnglese[row] 
      { 
       typeTextField.text = item 
      }else if seletedItemArray[row] == typeNewYork[row] 
      { 
       typeTextField.text = item 
      } 

      Picker2.isHidden = true 
     } 
     else if pickerView.tag == 2 
     { 
      qtyTextField.text = Qt[row].0 
      Picker3.isHidden = true 
     } 
    } 

    func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool { 
     if textField == cityTextField 
     { 
      self.Picker1.isHidden = false 
      typeTextField.text = "" 
      qtyTextField.text = "" 
     } 
     else if textField == typeTextField 
     { 
      Picker2.isHidden = false 
     } 
     else if textField == qtyTextField 
     { 
      Picker3.isHidden = false 
     } 
     return false 
    } 

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

Answer 1

Элементы из кортежа доступны в .0, .1 и т.д. Это, как вы бы вычислить ваш subtotal:

let picker2row = Picker2.selectedRow(inComponent: 0) 
let picker3row = Picker3.selectedRow(inComponent: 0) 

let subtotal = selectedItemArray[picker2row].1 * Qt[picker3row].1 

---

Если вы используете именованные кортежи:

var selectedItemArray = [(title: String, price: Double)]() 
var typeLasVegas: [(title: String, price: Double)] = [("City Tour $20.50", 20.50),("Museum $10.00", 10.00), ("Amusement Park $75.00",75.00)] 
var Qt: [(title: String, quantity: Double)] = [("1", 1.0),("2", 2.0),("3",3.0),("4", 4.0),("5",5.0),("6",6.0)] 

Тогда это немного лучше:

let subtotal = selectedItemArray[picker2row].price * Qt[picker3row].quantity