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

benjohnde

#!/bin/bash
git clone git@github.com:opencv/opencv.git
cd opencv
git checkout 3.3.0
python platforms/ios/build_framework.py ios \
  --dynamic \
  --without imgcodec --without videoio --without video --without calib3d --without features2d \
  --without objdetect --without dnn --without ml --without flann --without photo --without stitching \
  --without cudaarithm --without cudabgsegm --without cudacodec --without cudafeatures2d \
  --without cudafilters --without cudaimgproc --without cudalegacy --without cudaobjdetect \

brennanMKE

class EventEmitter

    /// Shared Instance.
    public static var sharedInstance = EventEmitter()

    // ReactNativeEventEmitter is instantiated by React Native with the bridge.
    private static var eventEmitter: ReactNativeEventEmitter!

    private init() {}

chourobin

Bridging Native & React for iOS & Android

js -> native

• Simple Example
• Callbacks
• Promises
• Properties

native -> js

rauschma

Advantages compared to using symbols as enum values:

• Enum values are much more customizable. For example, one can have custom prototype and/or instance methods.
• Enum values get two custom properties:
  • name provides direct access to the name of an enum value.
  • ordinal holds a number, the position of the enum value. Useful for some applications.
• One can use instanceof to test whether a value is an element of an enum.
• One occasionally requested feature for enums is that enum values be numbers (e.g. for flags) or strings (e.g. to compare with values in HTTP headers). That can be achieved by making those values properties of enum values. For an example, see enum Mode, below.

Static properties of enums:

ravishtiwari

app_identifier "com.yourorganization.mytodoapp" # The bundle identifier of your app
apple_id "<You Apple Id>" # Your Apple email address

# You can uncomment any of the lines below and add your own
# team selection in case you're in multiple teams
# team_name "CAMobileApp"
# team_id "Q2CBPJ58CA"

# you can even provide different app identifiers, Apple IDs and team names per lane:
# https://github.com/KrauseFx/fastlane/blob/master/docs/Appfile.md

akofman

#!/usr/bin/env node

/*
 * Disable bitcode for ios9 projects.
 * versions:
 *  xcode 0.8.2
 *  cordova-lib 5.3.3
 */

var xcode = require('xcode');

ColinEberhardt

/// An object that has some tear-down logic
public protocol Disposable {
  func dispose()
}


/// An event provides a mechanism for raising notifications, together with some
/// associated data. Multiple function handlers can be added, with each being invoked,
/// with the event data, when the event is raised.
public class Event<T> {

TimOliver

@implementation UIScrollView (ZoomToPoint)

/**
 Zooms into the specified point of the scroll view's zoomable content view at the supplied scaled.
 (The zoomable content view is the view that is returned in `viewForZoomingInScrollView:`
 
 @param zoomPoint - In terms of the scroll view's co-ordinate space, the point to zoom to
 @param scale     - A value between minimumZoomScale and maximumZoomScale in which to zoom to.
 @param animated  - Whether the transition is animated, or instant
 

staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

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This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

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