How to use Timer (NSTimer) in Swift: creating, stopping and repeating a timer

Hi! I just started learning Swift and am trying to implement a simple countdown timer in my app. I need the value on the screen to update every second, and the timer to stop after 10 seconds. I found the Timer class in the documentation, but I'm having issues. Here's what I'm trying to do: ```swift var seconds = 10 func startTimer() { Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(updateTimer), userInfo: nil, repeats: true) } @objc func updateTimer() { seconds -= 1 print(seconds) if seconds == 0 { // How to stop the timer? } } ``` The timer starts and counts down the seconds, but I don't understand: 1. How to properly stop the timer when `seconds` becomes 0? 2. Why does Xcode sometimes give a pr