A simple debounce handler for swift

DispatchQueue+Debounce.swift

//
//  DispatchQueue+Debounce.swift
//
//  Created by Abhishek Maurya on 22/05/24.
//

import Foundation

public extension DispatchQueue {
    func debounce(after interval: Int, action: @escaping (Any?) -> Void) -> (Any?) -> Void {
        var executed: Bool = false
        var lastFireTime: DispatchTime = .now()
        let dispatchDelay: DispatchTimeInterval = .milliseconds(interval)
        
        return { value in
            lastFireTime = .now()
            
            self.asyncAfter(deadline: .now()  + dispatchDelay) {
                let now: DispatchTime = .now()
                let when: DispatchTime = lastFireTime + dispatchDelay
                guard now.rawValue >= when.rawValue, !executed else { return }
                executed = true
                action(value)
            }
        }
    }
}

Usage.md

Usage:

let debouncedWorkItem = DispatchQueue.main.debounce(after: 2000) { value in
    print("Hello World", value ?? "")
}

for i in 0...5 {
    DispatchQueue.global().asyncAfter(deadline: .now() + TimeInterval(i)) {
        debouncedWorkItem(i)
    }
}

Will print Hello World 5