Updating a integer as a label in swift

I want to change the number value of a label by pressing a button. I used to get errors saying you can't put a number in a string, so, I did string(variable). It now displays the basic number, 1, but when I click it, it doesn't update!

Here is how I set up the variable:
First, I set up the button, to IBAction. Here is the code inside of it:

@IBOutlet weak var NumberOfExploits: UILabel!
@IBAction func exploiter(sender: AnyObject) {
var hacks = 0
hacks += 1
NumberOfExploits.text = String(hacks)
}


Can someone help be find out how to get it to change numbers?

3 Answers
3

First:

let is used for constants, these can not be changed.
var is used for variables.

let

var

Second:

Doing plus one is done with += 1 or with = myVariable + 1

+= 1

= myVariable + 1

var myVariable = 1

myVariable += 1
label.text = string(myVariable)


It is important to understand that your variables only live as long as the enclosing class or function is alive. So when you declare a variable, constant inside a function (using var let is a declaration) it will be be gone when the function is complete. A UIViewcontroller is there for as long as you want it to be. So declare things in there that you will need later.

var

let

UIViewcontroller

import UIKit

// things that live here are at the "global level"


// this is a viewcontroller. It is a page in your app.
class ViewController: UIViewController {

// things that live here are at the "class level"

var myClassCounter : Int = 0

// button in interfacebuilder that is connected through an outlet.
@IBOutlet weak var myButton: UIButton!


override func viewDidLoad() {
super.viewDidLoad()

// this is a function that gets called when the view is loaded
}

override func viewDidAppear(animated: Bool) {
// this is a function that gets called when the view appeared

}


// button function from interface builder
@IBAction func myButtonIsTouched(sender: AnyObject) {
// this will be destroyed when the function is done
var myFunctionCounter = 0
myFunctionCounter += 1

// this will be stored at class level
myClassCounter += 1
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}

}


You can also just do

label.text = "\(variable)"


which will display the number as string.

Most important declare the variable within the class but outside any function

var variable = 1


then write the IBAction function this way

IBAction

@IBAction func pressButton(sender : UIButton)
{
label.text = "(++variable)"
}


The syntax ++variable increments the variable by one.
The syntax "(v)" creates a string of anything which is string representable

++variable

"(v)"

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