How can I debounce a method call?

Question

I\'m trying to use a UISearchView to query google places. In doing so, on text change calls for my UISearchBar, I\'m making a request to google pla

Answer 1

Here is a debounce implementation for Swift 3.

https://gist.github.com/bradfol/541c010a6540404eca0f4a5da009c761

import Foundation

class Debouncer {

    // Callback to be debounced
    // Perform the work you would like to be debounced in this callback.
    var callback: (() -> Void)?

    private let interval: TimeInterval // Time interval of the debounce window

    init(interval: TimeInterval) {
        self.interval = interval
    }

    private var timer: Timer?

    // Indicate that the callback should be called. Begins the debounce window.
    func call() {
        // Invalidate existing timer if there is one
        timer?.invalidate()
        // Begin a new timer from now
        timer = Timer.scheduledTimer(timeInterval: interval, target: self, selector: #selector(handleTimer), userInfo: nil, repeats: false)
    }

    @objc private func handleTimer(_ timer: Timer) {
        if callback == nil {
            NSLog("Debouncer timer fired, but callback was nil")
        } else {
            NSLog("Debouncer timer fired")
        }
        callback?()
        callback = nil
    }

}