iOS Development - Timer App

Here, we are going to make a Timer app for an iOS, using Swift 3 and Xcode 8.

Open Xcode and create a new Single View Application and name it Timer (You can name it anything you like).

Click Main.StoryBoard.

Add a label to display the seconds (We are going to set 240 as default ). Resize it in Properties menu.

Add a navigation bar to the top and change the title of Timer.

Add two Bar buttons on the top navigation bar and change the System Item into play and pause.

Add a Toolbar to the bottom and rename the item to “-10”.

Add two bar button items and name them “Reset “and “+10”.

Click ViewController.Swift.

Now, control + drag label to the program and name it “timerLabel”.

Control + drag each button to the code and name them “play”,”pause”,”minusTen”,”plusTen”,”resetTimer”(Connection type must be Button).

Edit the code, as given below.

import UIKit
class ViewController: UIViewController {
var timer = Timer()
var time = 240
func decreaseTimer() {
if time > 0 {
time = time - 1
timerLabel.text = String(time)
} else {
timer.invalidate()
}
}
@IBOutlet weak
var timerLabel: UILabel!@IBAction func play(_ sender: Any) {
timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(ViewController.decreaseTimer), userInfo: nil, repeats: true)
}
@IBAction func pause(_ sender: Any) {
timer.invalidate()
}
@IBAction func minusTen(_ sender: Any) {
if time > 10 {
time -= 10
timerLabel.text = String(time)
}
}
@IBAction func plusTen(_ sender: Any) {
time += 10
timerLabel.text = String(time)
}
@IBAction func resetTimer(_ sender: Any) {
time = 240
timerLabel.text = String(time)
}
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.
}
}

Now, run the app.