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

Sorix

//
//  ColorableNavigationController.swift
//
//  Created by Vasily Ulianov on 26.10.16.
//
import UIKit

/// Navigation bar colors for `ColorableNavigationController`, called on `push` & `pop` actions
public protocol NavigationBarColorable: class {
	var navigationTintColor: UIColor? { get }

wholmgren

git config --global diff.tool bbdiff
git config --global difftool.bbdiff.cmd 'bbdiff --wait --resume "$LOCAL" "$REMOTE"'
git config --global difftool.prompt false

git config --global merge.tool bbdiff
git config --global mergetool.bbdiff.cmd 'bbdiff --wait --resume "$LOCAL" "$REMOTE"'

Double check ~/.gitconfig 

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.

OdNairy

// Source: https://devforums.apple.com/message/866487#866487

typedef int (*PYStdWriter)(void *, const char *, int);

static PYStdWriter _oldStdWrite;

int __pyStderrWrite(void *inFD, const char *buffer, int size)
{
    if ( strncmp(buffer, "AssertMacros: queueEntry", 24) == 0 ) {
        return 0;

nolanw

#!/bin/bash

# ios-configure runs a "configure" script using the iOS 4.3 SDK, generating a 
# static library that will load and run on your choice of iPhone, iPad, and 
# their respective simulators.
#
# Simply run in the same directory as a "configure" script.
# You can run this script for multiple targets and use lipo(1) to stitch them 
# together into a universal library.
#