iOS & macOS development

Recently, I came across this post and fell in love with the idea of using XCode 4 snippets. Up until I read the post, I had heard they existed, but never really tried them. After reading the post, I began using his snippets as well as started creating my own. Now, I would say that my work-flow is faster than ever.

There is a very nice feature in Instruments that helps you to point your loupe to a very precise spot in your code.

This is the second part of a two part tutorial series on using ARC in iOS 5.
In the first part of the series, we covered how ARC works and how to convert projects to use ARC with Xcode’s built in conversion utility.
In this second and final part of the series, we’ll cover how to convert files by hand, ARC as it relates to Core Foundation, weak properties, and much more!

A lightweight Objective-C framework for Cocoa Touch to create UIKit view hierarchies in XML.

A Very High Performance Objective-C JSON Library

Learn Cocoa: Featured tutorials from Cocoa Dev Central

I recently noticed this question about different-colored spinning progress indicators on Stack Overflow, and finally got around to giving my answer. I’m not sure if the original question was answered satisfactorily by using a UIActivityIndicatorView, but I hope my code can be useful to someone.

I have implemented two different clones of the spinning NSProgressIndicator, which can be drawn at any size and in any color. One is a subclass of NSView, and can be used on OS X 10.4, and the other is a subclass of CALayer, and can be used in a CoreAnimation-based project on OS X 10.5, and presumably on an iPhone (though I haven’t actually tested that yet).

I put the code up on github (both the NSView-based version and the CoreAnimation-based one), under the BSD license. They each include the spinning progress indicator classes and an example app showing how they can be used. The code should be pretty straight-forward. One caveat is that they might not be super fast performance-wise, but should be good for most uses.

✔ Sources: https://github.com/kelan/yrk-spinning-progress-indicator-layer

HGPageScrollView - UIScrollView for iPhone with horizontal paging like mobile Safari tabs.

An extension of iOS UIScrollView that allows scrolling of multiple pages, like mobile Safari tab viewer.

HGPageScrollView uses a similar methodology to UITableView. It defines both a dataSource and a delegate, which its client can implement. At the very least HGPageScrollView expects its dataSource to provide HGPageViews to display.

Like UITableView, HGPageScrollView provides a way to improve performance by reusing pages. It maintains a queue of pages that the data source has marked for reuse. A page is marked for reuse by assigning a value to its reuseIdentifier.

The most disruptive change in iOS 5 is the addition of Automatic Reference Counting, or ARC for short. ARC is a feature of the new LLVM 3.0 compiler and it completely does away with the manual memory management that all iOS developers love to hate.

Recreating the buttonless interaction pattern found in Clear for iPhone app.

To be successful on the App Store, your app needs to stand out. The vanilla user-interface “look and feel” provided by Apple just doesn’t cut it any more in a crowded market.

Many of the most popular apps on the App Store present standard iOS UI elements in a non-standard fashion:
Twitter employs a custom UITabBar
Instagram uses both a custom UITabBar and a custom UINavigationBar
Epicurious for iPad customizes elements of the standard split-view interface

Prior to iOS 5, many developers had to take somewhat unconventional approaches to achieve these results. Although subclassing and overriding drawRect: was the recommended approach, many resorted to the dreaded “method swizzling”.
But with iOS 5, those dark days are over! iOS 5 has included many new APIs you can use to easily customize the appearance of various UIKit controls.

To illustrate some of these new APIs, in this tutorial we’re going to take a “plain vanilla” app about surfing trips and customize the UI to get a more “beach-themed” look-and-feel.

StackKit is a Cocoa framework used to interact with the Stack Exchange API (used by Stack Overflow, Super User, Server Fault, Stack Exchange, and related websites).