Creating a class that does all of the functions of the viewcontroller - ios

Question

I am attempting to make my calculator function look more organized. I have decided to create a calculator class that does all of the functions. Currently this is not working, my only problem is that I make a new instance of a class every time a number is pressed, this happens because I dont know what number is going to be pressed next so I cannot define LBLOutput in my constructor until It is passed to me. Here are my two files
The problem lies where I am calling the cb.functions. Currently they work but only one number can show up on the screen at a time due to the fact that a new class is declared every time.
Is this a viable way of making the calculator? Do i need to just start from scratch?
//
// ViewController.swift
// MyCalculator
//
// Created by Kevin Maldjian on 2/6/17.
// Copyright © 2017 Kevin Maldjian. All rights reserved.
//
import UIKit
import Foundation
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
}
#IBOutlet weak var LBLOutput: UILabel!
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
#IBAction func btrNumberClick(_ sender: UIButton) {
let cb = calculatorBrain(LBLOutput: LBLOutput , sender: sender)
cb.btrNumberClick()
}
#IBAction func clearTheLabel(_ sender: Any) {
let cb = calculatorBrain(LBLOutput: LBLOutput, sender: sender as! UIButton)
cb.clearTheLabel()
}
#IBAction func goNegative(_ sender: Any){
let cb = calculatorBrain(LBLOutput: LBLOutput, sender: sender as! UIButton)
cb.goNegative()
}
#IBAction func squareRoot(_ sender: Any) {
let cb = calculatorBrain(LBLOutput: LBLOutput, sender: sender as! UIButton)
cb.squareRoot()
}
}
THE MAIN FUNCTIONS ARE DONE HERE
//
// calculatorBrain.swift
// SalvageAttempt
//
// Created by Kevin Maldjian on 3/13/17.
// Copyright © 2017 Kevin Maldjian. All rights reserved.
//
import Foundation
import UIKit
class calculatorBrain
{
var num1 = ""
var num2 = ""
var finalString = ""
var isFirstNumber = true
var safeToAdd = true
var hasFinalString = false
var isClear = true
var hasDecimal = false
var doubleChecker = 0
var hasSecondDecimal = false
var LBLOutput = UILabel()
var sender = UIButton()
init(LBLOutput : UILabel, sender : UIButton) {
self.num1 = " "
self.num2 = " "
self.finalString = ""
self.isFirstNumber = true
self.safeToAdd = true
self.hasFinalString = false
self.isClear = true
self.hasDecimal = false
self.doubleChecker = 0
self.hasSecondDecimal = false
self.LBLOutput = LBLOutput
self.sender = sender
}
func btrNumberClick() {
if isClear {
LBLOutput.text = ""
isClear = false
}
let currentText = LBLOutput.text!
let textLabel = sender.titleLabel?.text
if let text = textLabel {
switch text {
case "+", "x", "/", "-","%":
if hasFinalString {
return
}
finalString = text
isFirstNumber = false
hasFinalString = true
safeToAdd = true
LBLOutput.text = "\(currentText) \(finalString) "
break
case "=":
if !hasFinalString
{break}
isFirstNumber = true
hasFinalString = false
isClear = true
var result = calculate()
if result.truncatingRemainder(dividingBy:1) == 0
{
result = (result)
}
LBLOutput.text = "\(result)"
num1 = "\(result)"
safeToAdd = false
hasSecondDecimal = false
hasDecimal = false
break
case ".":
if !safeToAdd{
num1 = ""
LBLOutput.text = ""
num1 = "\(num1)\(text)"
LBLOutput.text = LBLOutput.text! + num1
safeToAdd = true
} else if isFirstNumber{
if hasDecimal
{break}
LBLOutput.text = ""
num1 = "\(num1)\(text)"
LBLOutput.text = LBLOutput.text! + num1
hasDecimal = true
}else{
if hasSecondDecimal
{break}
num2 = "\(num2)\(text)"
LBLOutput.text = "\(currentText)\(text)"
hasSecondDecimal = true
}
break
default:
if !safeToAdd{
num1 = ""
LBLOutput.text = ""
num1 = "\(num1)\(text)"
LBLOutput.text = LBLOutput.text! + num1
safeToAdd = true
} else if isFirstNumber{
LBLOutput.text = ""
num1 = "\(num1)\(text)"
LBLOutput.text = LBLOutput.text! + num1
}else{ num2 = "\(num2)\(text)"
LBLOutput.text = "\(currentText)\(text)"
}
break;
}
}
}
func goNegative(){
var negativeChecker = Double(num1)!
if negativeChecker > 0
{ num1 = ("-" + num1)
LBLOutput.text = num1
}else{
negativeChecker = (-2 * negativeChecker) + negativeChecker
num1 = String(negativeChecker)
LBLOutput.text = String(negativeChecker)
}
}
func squareRoot() {
let squareRootX = sqrt(Double(LBLOutput.text!)!)
num1 = String(squareRootX)
LBLOutput.text = String(squareRootX)
}
#IBAction func clearTheLabel() {
num1 = ""
num2 = ""
LBLOutput.text = "0"
isClear = true
}
func calculate() -> Double {
let firstNumber = Double(self.num1)!
let secondNumber = Double(self.num2)!
num1 = ""
num2 = ""
self.isClear = false
switch finalString {
case "+":
return firstNumber + secondNumber
case "-":
return firstNumber - secondNumber
case "x":
return firstNumber * secondNumber
case "/":
return firstNumber / secondNumber
case "%":
return (firstNumber * 100) / secondNumber
default:
return 0
}
}
}

Answer 1

Move all of your functions out of this class called "calculatorBrain". Just make them public, or in the case of a separate target (like a Framework) open. For instance:
class MyVC:UIViewController {
let a:Float = 1.0
let b:Float = 1.0
let currentSum = sum(a,b)
print(currentSum) // displays 2.0
}
In a separate file:
public sum(var1:Float, var2:Float) {
return var1+var2
}
Not much more to it. Again, remove everything from a class and you won't need an instance.