# How to repeat a task repeatedly after a regular interval in Swift(iOS)?

iOSApps/ApplicationsMobile Development

In this post we will learn how to repeat a task after a regular interval.

In this example we will update a label after a particular interval of time repeatedly.

In iOS we user Timer to achieve this task. Lets get started

Step 1 − Open Xcode → New Project → Single View Application → Let’s name it “Timer”

Step 2 − Open Main.storyboard and add a label as shown below.

Step 3 − Attach one @IBOutlet for the bottom label. Name it timerLabel

Step 4 − We will show the seconds since when the app is launched on the label. So, declare two variables in view controller as follows.

var timeLaunched: Int = 0
var timer: Timer?

Step 5 − Add a function that updates the label. We will call this function repeatedly at regular intervals afterwards.

@objc func updateLabel() {
timerLabel.text = " Time Launched = \(timeLaunched) Seconds "
timeLaunched += 1
}

As you can see this function increments the time launched and shows it on the label.

Step 6 − Initialize and trigger the timer. In viewDidLoad of ViewController initialize the timer and call the function updateLabel at regular intervals. Here we are triggering the function at every 1 second. You can trigger the function based on your requirement.

override func viewDidLoad() {
}