tclementdev

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

nathanfjohnson

// Swift 4
// Check out the history for contributions and acknowledgements.

extension String {
  /// Returns a new string made by replacing all HTML character entity references with the corresponding character.
  ///
  /// - Returns: decoded string
  func decodingHTMLEntities() -> String {
    var result = String()
    var position = startIndex

adamcichy

extension CGImage {
    var isDark: Bool {
        get {
            guard let imageData = self.dataProvider?.data else { return false }
            guard let ptr = CFDataGetBytePtr(imageData) else { return false }
            let length = CFDataGetLength(imageData)
            let threshold = Int(Double(self.width * self.height) * 0.45)
            var darkPixels = 0
            for i in stride(from: 0, to: length, by: 4) {
                let r = ptr[i]

morhekil

[iOS - Swift] How to communicate with iFrames inside WebView

One of the core technologies at the heart of Onefill is its ability to auto-fill even the most complex form on a website with 100% precision, with a single tap. And the techology that built does allow us to do just that, but with one exception - iframes.

And while you might think that iframes are a thing of the past (who would use them these days, right?) - the reality is that they're often powering some of the most critical piece of functionality there is on online store - its payment

fedorsemenchenko

#import <Foundation/Foundation.h>

typedef void (^KeyboardVisabilityWillChange)(BOOL isVisible);

@interface DBO_KeyboardManager : NSObject

@property (assign, nonatomic, readonly) CGRect keyboardFrame;
@property (strong, nonatomic, readonly) NSNumber *animationDuration;

@property (nonatomic, copy) KeyboardVisabilityWillChange keyboardVisabilityChange;

NinoScript

//: Playground - noun: a place where people can play

import Cocoa

enum Enum {
    case SimpleCase
    case AssociatedValue(String)
    case AnotherAssociated(Int)
}
extension Enum {

satoshin2071

/*
 From http://alisoftware.github.io/swift/pattern-matching/2016/05/16/pattern-matching-4/
 
 Shakyo practice
 
 Pattern Matching, Part 4: if case, guard case, for case
 */


import XCPlayground

gonzalezreal

iOS Cell Registration & Reusing with Swift Protocol Extensions and Generics

A common task when developing iOS apps is to register custom cell subclasses for both UITableView and UICollectionView. Well, that is if you don’t use Storyboards, of course.

Both UITableView and UICollectionView offer a similar API to register custom cell classes:

public func registerClass(cellClass: AnyClass?, forCellWithReuseIdentifier identifier: String)
public func registerNib(nib: UINib?, forCellWithReuseIdentifier identifier: String)

jwliechty

#/bin/bash 

export MY_EXPORTED_VAR="Boo Yeah!"
MY_NON_EXPORTED_VAR="You won't see this one!"

# This script was inspired by the answer to the question in
# http://unix.stackexchange.com/questions/50692/executing-user-defined-function-in-a-find-exec-call

runFindCommand(){
  # 'myFunct "$@"' will call the function with the arguments passed into the shell

arturlector

Вопросы на собеседование iOS разработчика (дополненное издание):

General:

• Что такое полиморфизм?

• Что такое *инкапсуляция? Что такое *нарушение инкапсуляции?

• Чем абстрактный класс отличается от интерфейса?

• Расскажите о паттерне MVC. Чем отличается пассивная модель от активной?