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@lukaspili
lukaspili / ScrollableViewController.swift
Last active March 17, 2023 12:35
Scroll view snap kit
import UIKit
import SnapKit
class ScrollableViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = UIColor.whiteColor()
let scrollView = UIScrollView()
@Sorix
Sorix / AsynchronousOperation.swift
Last active May 22, 2024 07:15
Subclass of NSOperation (Operation) to make it asynchronous in Swift 3, 4, 5
// Created by Vasily Ulianov on 09.02.17, updated in 2019.
// License: MIT
import Foundation
/// Subclass of `Operation` that adds support of asynchronous operations.
/// 1. Call `super.main()` when override `main` method.
/// 2. When operation is finished or cancelled set `state = .finished` or `finish()`
open class AsynchronousOperation: Operation {
public override var isAsynchronous: Bool {
import Foundation
import PlaygroundSupport
/// A thread-safe array.
public class SynchronizedArray<Element> {
private let queue = DispatchQueue(label: "io.zamzam.ZamzamKit.SynchronizedArray", attributes: .concurrent)
private var array = [Element]()
public init() { }
@tclementdev
tclementdev / libdispatch-efficiency-tips.md
Last active November 15, 2024 01:56
Making efficient use of the libdispatch (GCD)

libdispatch efficiency tips

The libdispatch is one of the most misused API due to the way it was presented to us when it was introduced and for many years after that, and due to the confusing documentation and API. This page is a compilation of important things to know if you're going to use this library. Many references are available at the end of this document pointing to comments from Apple's very own libdispatch maintainer (Pierre Habouzit).

My take-aways are:

  • You should create very few, long-lived, well-defined queues. These queues should be seen as execution contexts in your program (gui, background work, ...) that benefit from executing in parallel. An important thing to note is that if these queues are all active at once, you will get as many threads running. In most apps, you probably do not need to create more than 3 or 4 queues.

  • Go serial first, and as you find performance bottle necks, measure why, and if concurrency helps, apply with care, always validating under system pressure. Reuse

import Alamofire
import CoreTelephony
enum NetworkType {
case unknown
case noConnection
case wifi
case wwan2g
case wwan3g
case wwan4g