Create calculator history array swift - ios

Question

I have created a calculator and have created a Model.swift to handle all of my calculations. Then everything else is handled in my ViewController.swift. I'm trying to add another functionality, I am looking to create a history of all the operations performed in my calculator i have made and store them in an array.
Here is my code so far:
ViewController.swift
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var displayLabel: UILabel!
#IBOutlet weak var HistoryLabel: UILabel!
var historyArray: [String] = []
var userIsTypingNumbers = false
var firstNumber = 0
var secondNumber = 0
#IBAction private func NumbersEntered(_ sender: UIButton) {
//know what number is being pressed
/*let digit = sender.currentTitle!
//if user is typing a number, do this.
if userIsTypingNumbers{
//specify what number is being pressed
let textCurrentDisplay = displayLabel.text!
//append the another number onto the previous number.
displayLabel.text = textCurrentDisplay + digit
} else {
displayLabel.text = digit
}
userIsTypingNumbers = true*/
/*addToHistory(recordToAddToHistory: digit)*/
let number = sender.currentTitle
if userIsTypingNumbers {
displayLabel.text = displayLabel.text! + number!
} else {
displayLabel.text = number
userIsTypingNumbers = true
}
}
var displayValue: Double {
get {
return Double(displayLabel.text!)!
}
set {
displayLabel.text = String(newValue)
}
}
private var calculations = PerformCalculations()
#IBAction func Enter(_ sender: UIButton) {
//perform the calculations
if userIsTypingNumbers{
calculations.setOperand(operand: displayValue)
userIsTypingNumbers = false
}
if let mathematicalSymbol = sender.currentTitle {
calculations.performOperation(symbol: mathematicalSymbol)
/*addToHistory(recordToAddToHistory: String(mathematicalSymbol))*/
}
/*HistoryLabel.text = HistoryLabel.text! + String(sender.currentTitle!)*/
displayValue = calculations.result
/*HistoryLabel.text = HistoryLabel.text! + String(displayValue)*/
/*historyArray.append("\(String(describing: HistoryLabel.text))")*/
}
#IBAction func Clear(_ sender: UIButton) {
//clear display to 0.
displayLabel.text = "0"
HistoryLabel.text = ""
}
#IBAction func Delete(_ sender: UIButton) {
//deleting last typed number, if user messed up.
let name: String = self.displayLabel.text!
//count number of characters.
let stringLength = name.characters.count
let substringIndex = stringLength - 1
displayLabel.text = (name as NSString).substring(to: substringIndex)
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
/*override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if (segue.identifier == "History"){
if let destinationVC = segue.destination as? HistoryClassViewController{
destinationVC.someData = HistoryLabel.text
}
}
}*/
}
Model.swift
import Foundation
enum Optional<T>{
case None
case Some(T)
}
class PerformCalculations {
private var accumulator = 0.0
func setOperand(operand: Double){
accumulator = operand
}
//performing the operations for various operands
private var operations: Dictionary<String, Operation> = [
"√" : Operation.UnaryOperation(sqrt), //sqrt,
"×": Operation.BinaryOperation({$0 * $1}),
"+": Operation.BinaryOperation({$0 + $1}),
"-": Operation.BinaryOperation({$0 - $1}),
"÷": Operation.BinaryOperation({$0 / $1}),
"=": Operation.Equals
]
//case for various operands
private enum Operation{
case Constant(Double)
case UnaryOperation((Double) -> Double)
case BinaryOperation((Double, Double) -> Double)
case Equals
}
//switch case to actually perform the operations
func performOperation(symbol: String){
if let operation = operations[symbol]{
switch operation{
case .Constant(let value): accumulator = value
case .BinaryOperation(let function):
executePendingBinaryOperation()
pendingVar = PendingBianryOperationInfo(binaryFunction: function, firstOperand: accumulator)
case .UnaryOperation(let foo): accumulator = foo(accumulator)
case .Equals:
executePendingBinaryOperation()
}
}
}
private func executePendingBinaryOperation(){
if pendingVar != nil{
accumulator = pendingVar!.binaryFunction(pendingVar!.firstOperand,accumulator)
pendingVar = nil
}
}
private var pendingVar: PendingBianryOperationInfo?
private struct PendingBianryOperationInfo{
var binaryFunction: (Double, Double) -> Double
var firstOperand: Double
}
var result: Double{
get{
return accumulator
}
}
}
Any help would be appreciated, thank you very much!

Answer 1

I have solved my problem. Here is the updated code, incase it ever comes in handy for someone.
ViewController.swift
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var displayLabel: UILabel!
#IBOutlet weak var HistoryLabel: UILabel!
var historyArray: [String] = []
var userIsTypingNumbers = false
var firstNumber = 0
var secondNumber = 0
var operation = ""
var result = 0.0
#IBAction private func NumbersEntered(_ sender: UIButton) {
//know what number is being pressed
let number = sender.currentTitle
//if user is typing number, do this.
if userIsTypingNumbers {
//specify what number is being pressed.
//append the number onto the previous number.
displayLabel.text = displayLabel.text! + number!
} else {
displayLabel.text = number
userIsTypingNumbers = true
}
}
var displayValue: Double {
get {
return Double(displayLabel.text!)!
}
set {
displayLabel.text = String(newValue)
}
}
private var calculations = PerformCalculations()
#IBAction func OperationsPressed(_ sender: UIButton) {
userIsTypingNumbers = false
firstNumber = Int(Double(displayLabel.text!)!)
operation = sender.currentTitle!
if operation == "√" {
result = (PerformCalculations().squareroot(a: Double(firstNumber)))
displayLabel.text = String(result)
}
}
#IBAction func Enter(_ sender: UIButton) {
userIsTypingNumbers = false
secondNumber = Int(Double(displayLabel.text!)!)
if operation == "+" {
result = (PerformCalculations().add(a: Double(firstNumber), b: Double(secondNumber)))
} else if operation == "÷" {
result = (PerformCalculations().division(a: Double(firstNumber), b: Double(secondNumber)))
} else if operation == "×" {
result = (PerformCalculations().multiplication(a: Double(firstNumber), b: Double(secondNumber)))
} else if operation == "-" {
result = (PerformCalculations().subtract(a: Double(firstNumber), b: Double(secondNumber)))
}
displayLabel.text = String(result)
historyArray.append("\(firstNumber) \(operation) \(secondNumber) = \(result)")
userIsTypingNumbers = false
//self.performSegue(withIdentifier: "History", sender: self)
}
#IBAction func Clear(_ sender: UIButton) {
//clear display to 0.
displayLabel.text = "0"
}
#IBAction func Delete(_ sender: UIButton) {
//deleting last typed number, if user messed up.
let name: String = self.displayLabel.text!
//count number of characters.
let stringLength = name.characters.count
let substringIndex = stringLength - 1
displayLabel.text = (name as NSString).substring(to: substringIndex)
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
/*override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "History" {
if let destinationVC = segue.destination as? TableTableViewController {
destinationVC.dataString = historyArray.description
}
}
}*/
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let destViewController : TableTableViewController = segue.destination as! TableTableViewController
destViewController.dataString = historyArray.description
}
}
Model.swift
import Foundation
class PerformCalculations {
func add(a: Double, b: Double) -> Double {
let result = a + b
return result
}
func division(a: Double, b: Double) -> Double {
let result = a / b
return result
}
func subtract(a: Double, b: Double) -> Double {
let result = a - b
return result
}
func multiplication(a: Double, b: Double) -> Double {
let result = a * b
return result
}
func squareroot(a: Double) -> Double {
let result = sqrt(a)
return result
}
}