nicklockwood

Hacking UIView animation blocks for fun and profit

In this article, I'm going to explore a way that we can create views that implement custom Core Animation property animations in a natural way.

As we know, layers in iOS come in two flavours: Backing layers and hosted layers. The only difference between them is that the view acts as the layer delegate for its backing layer, but not for any hosted sublayers.

In order to implement the UIView transactional animation blocks, UIView disables all animations by default and then re-enables them individually as required. It does this using the actionForLayer:forKey: method.

Somewhat strangely, UIView doesn't enable animations for every property that CALayer does by default. A notable example is the layer.contents property, which is animatable by default for a hosted layer, but cannot be animated using a UIView animation block.

Rathgore

import Foundation

let SEED: UInt16 = 0xFFFF

let crcCCITTLookupTable: [UInt16] = [
    0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50A5, 0x60C6, 0x70E7, 0x8108,
    0x9129, 0xA14A, 0xB16B, 0xC18C, 0xD1AD, 0xE1CE, 0xF1EF, 0x1231, 0x0210,
    0x3273, 0x2252, 0x52B5, 0x4294, 0x72F7, 0x62D6, 0x9339, 0x8318, 0xB37B,
    0xA35A, 0xD3BD, 0xC39C, 0xF3FF, 0xE3DE, 0x2462, 0x3443, 0x0420, 0x1401,
    0x64E6, 0x74C7, 0x44A4, 0x5485, 0xA56A, 0xB54B, 0x8528, 0x9509, 0xE5EE,

JaviLorbada

Videos

• Introduction to Functional Programming Johannes Weiß - https://vimeo.com/100786088
• ReactiveCocoa at MobiDevDay Andrew Sardone - https://vimeo.com/65637501
• The Future Of ReactiveCocoa Justin Spahr-Summers - https://www.youtube.com/watch?v=ICNjRS2X8WM
• Enemy of the State Justin Spahr-Summers - https://www.youtube.com/watch?v=7AqXBuJOJkY
• WWDC 2014 Session 229 - Advanced iOS Application Architecture and Patterns Andy Matuschak - https://developer.apple.com/videos/play/wwdc2014/229/
• Functioning as a Functionalist Andy Matuschak - https://www.youtube.com/watch?v=rJosPrqBqrA
• Controlling Complexity in Swift Andy Matuschak - https://realm.io/news/andy-matuschak-controlling-complexity/

natecook1000

Greetings and salutations, NSHipsters!

As the year winds down, it's a tradition here at NSHipster to ask you, dear readers, to offer up your favorite tricks and tips from the past year as gifts to your fellow hipsters. With iOS 9, El Capitan, brand new watch- and tvOS's, and the open-sourcing of some minor Apple-related tech, there's bound to be lots to share.

Submit your favorite piece of Swift or @objc trivia, helpful hints, unexpected discoveries, useful workarounds, useless fascinations, or anything else you found cool this year. Just comment below!

If you need inspiration, try [the list from last year][2015], or [from the year before][2014], or [from the year before that][2013].

ilyapuchka

// The issue with sectionHeadersPinToVisibleBounds and sectionFootersPinToVisibleBounds is that they do not pin 
// first header and last footer when bouncing. This layout subclass fixes that.

class StickyLayout: UICollectionViewFlowLayout {
    
    override init() {
        super.init()
        self.sectionFootersPinToVisibleBounds = true
        self.sectionHeadersPinToVisibleBounds = true
    }

robertpainsi

Commit Message Guidelines

Short (72 chars or less) summary

More detailed explanatory text. Wrap it to 72 characters. The blank
line separating the summary from the body is critical (unless you omit
the body entirely).

Write your commit message in the imperative: "Fix bug" and not "Fixed
bug" or "Fixes bug." This convention matches up with commit messages

u10int

import Foundation
import UIKit


/// Used to create a layout guide that pins to the top of the keyboard
final class KeyboardLayoutGuide {

    private let notificationCenter: NotificationCenter
    private let bottomConstraint: NSLayoutConstraint

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

chriseidhof

//
//  ContentView.swift
//  DeleteMe
//
//  Created by Chris Eidhof on 02.02.21.
//

import SwiftUI

/*

mecid

import SwiftUI

extension Calendar {
    func generateDates(
        inside interval: DateInterval,
        matching components: DateComponents
    ) -> [Date] {
        var dates: [Date] = []
        dates.append(interval.start)