A year ago I analyzed how many built-in apps in iOS 10.1 and macOS 10.12 were using Swift: Apple’s use of Swift in iOS 10.1 and macOS 10.12.

How many built-in apps are using Swift in iOS 11.1 and macOS 10.13.1? Let’s find it out!

In Xcode 9 Apple quietly introduced a new build system. This is a “preview” and is not enabled by default. It promises improvements in build times as well as changes to how object dependencies in Swift are handled.

Circular dependencies have long been a major pain point for Swift developers. They can cause unpredictable behavior when editing, long build times, and Xcode crashes.

The one concept Nietzsche, Thoreau and Hesse most probably tried to elude through their lives: Dependency. Even if one does not agree or embrace their philosophies, a programmer should — or must? — apply their way of thinking while programming.

This time I wanted to talk about how to mock UIApplication, or any other library for unit testing. When you are writing unit tests you want to be in control. With a specific input the output must always be what you expect. That is the main reason why you shouldn’t do network requests in unit tests. You don’t want your tests to fail for poor network connection. That’s also why you have to do some extra work with system or 3rd party libraries. But how can you trust an output of a function that uses a system library? You cannot inject the dependency for the class since the source is out of your control. How can you work around this problem? How to make the module testable so that you control the outputs?

An alternative layout framework, a balanced medium between manual layout and auto layout. Great for calculating frames with FlightAnimator!!

Updated for iOS 11 and Swift. Tools and APIs required to build applications for the iPhone and iPad platforms using the iOS SDK. User interface design for mobile devices and unique user interactions using multi-touch technologies. Object-oriented design using model-view-controller paradigm, memory management, Swift programming language. Other topics include: object-oriented database API, animation, mobile device power management, multi-threading, networking and performance considerations.

If you have an iPhone, go to the App Store and navigate to Updates. You’ll see release notes describing changes developers have made to the newest versions of the apps on your phone. But sometimes, a note will stand out. Scrolling through my own recently, I came across this one written for a transportation app called Transit that I often use here in New York City.