I’m currently working on outfitting an app I’m working on to be able to validate receipts to verify purchases of the app. Little did I know, this adventure would introduce the need to understand how to use cryptography in order to work with the receipt. Cryptography library needed In order to even “...

In a previous “Testability Tip for Swift Developers”, I discussed the principle of observability. “If it’s observable, it’s testable” was the primary conclusion of the article, and I pointed toward using the public access control modifier for parts of your app that you intend to test. In this editio...

Updated on June 13, 2017 – Swift 3.0, Xcode 8 Code re-use is a powerful thing, but it’s not always easy to pull off. We strive for it though, because in the long run, it makes maintaining the code far, far easier than if we just settled for copying and pasting. With the introduction of dynamic frame...

Following along with Steve Smith’s “Your First ASP.NET 5 Application on a Mac”, I found myself frustrated that, despite all my efforts, the simple little sample project I was trying to get running just wouldn’t work due to a problem with restoring the project’s dependencies. Retracing my steps I got...

Being a C# developer by day and a Swift developer by night has me constantly thinking about the similarities and differences between these two languages. I genuinely enjoy programming with each, and I love it when I can take a strategy that works well in one language, and see where that might cross ...

The old adage “Don’t go reinventing the wheel” comes into play often when developing software, doesn’t it? Why build this [thing] ourselves when someone else has invented it already? Fantastic libraries and frameworks exist out there to assist developers with common and sometimes even difficult prob...

I’m very excited to announce that my new app, 10 Read 10 Said, is now available for iOS and Android! While the goal of the app is to help you implement the “10 Read 10 Said” strategy for memorizing Bible verses, my goal in this article is to dissect the app, and share with you how some of the major ...

Data management applications, by which I mean an app where you’re allowing users to add, edit, and delete bits of data as part of your app’s core function, very likely use a table view (or two) to visualize lists of information that users of the app can interact with. Making changes to the informati...

Updated on April 17, 2017 – Swift 3 Circular progress indicators are a nice and compact way to visualize progress information for users of your iOS app. I was extremely grateful to come across Kaan Dedeoglu’s KDCircularProgress project on GitHub. It’s a versatile little UI component written in Swift...

As I listened to the WWDC15 talk on Building Better Apps with Value Types in Swift I was struck by a sentence that I had never dawned on me before: Every Value Type should be Equatable. That is, every Value Type should conform to the Equatable protocol. Talk about a sweeping statement! Wow – every V...

I’ll say it up front – I’m not a great designer. What tends to happen with me and projects is that I end up saving all-things color until the end of a project. You know… the old procrastinator’s motto: “If you don’t get it done today and tomorrow doesn’t come, then you ain’t gotta do it!” So the oth...

Updated on April 19, 2016 – Swift 2.1 | Added example project Apple’s Event Kit framework empowers developers to interact with an iOS device’s calendar database. Not only can we read calendars and events from the database, we can also create calendars. In a previous article, we looked at how to hand...

One of the most exciting things that’s come out of WWDC 2015 is the fact that unit testing in Swift has been greatly simplified. The latest announcements have actually rendered a few of my articles on the subject obsolete, once Xcode 7 is in full circulation among the Swift developer community. If y...

The sequence of accessing a UINavigationController's first child from within the AppDelegate or within prepareForSegue(_:sender:) always gets me. Here are a few quick snippets to help you and I quickly get up and running when working with navigation controllers in our Swift applications: AppDelegate...

Updated on September 23, 2015 – Swift 2.0 My goal with this article is to help you utilize the full power of NSFetchedResultsController. This is a continuation on a series of articles I’ve written on Core Data and NSFetchedResultsController, so you may want to check out those previous posts to get a...

Think of this screencast as the “Hello World” of creating a view controller with a table view. I cover organizing things in the Storyboard, Auto Layout constraints, and the implementation of the data source protocol methods for a table view. Screencast Screencast Transcript [0:01] Hi, I’m Andrew fro...

Updated on October 26, 2016 – Swift 3.0 EventKit provides a set of classes for accessing and manipulating a user’s calendar events and reminders. In the tutorial that follows, my goal is to walk you through the first steps of setting up an app that utilizes EventKit. I will demonstrate how to reques...

I’m willing to bet that a good number of Swift developers struggle with the particulars of how strong, weak, and unowned affect the run-time behavior of their code. I, myself, wouldn’t want to have to give an explanation of the finer points of Automatic Reference Counting (ARC) if my life depended o...

Scenario This may be an edge case, but I spent enough time (a couple of days) spinning on this that I thought it warranted a signpost on the Internet. Suppose you have the following scenario before you: Basics You’re building an ASP.Net web application Entity Framework has been chosen as your ORM SQ...

The principle of science, the definition, almost, is the following: The test of all knowledge is experiment. The sole test of the validity of any idea is experiment. These quote came from Chapter 1 and Chapter 2 of the Feynman Lectures on Physics. I’m not a physicist, but the software developer in m...

As it turns out, Swift isn’t C# (or Java or VB.Net or…)! My day job keeps me busy writing C#, so I’ll reference it as my go-to comparison language for this article. The conclusion, however, carries over to other languages that have access control modifiers. I just spent the greater part of a week ex...

How often do we take an initial cursory look at some documentation, shake our heads and say, “Ok, sure! Got it!”, and then some time later get to the actual usage of that perceived understanding only to find out, “Woah – this is behaving differently than I expected! I wonder if the documentation say...

Quite often in unit testing, especially when practicing Test-Driven Development, I find myself wanting to test every single line of code. When I run up against a private function, however, I often scratch my head and ask, “How am I supposed to test this??”. Most experienced testers will tell you, “D...

Updated on October 11, 2016 – Swift 3.0 Delegation can be a difficult topic to wrap your head around. I found it easiest to break up posts on the topic to help readers who are new to the pattern grasp the concepts a little better. First, I analyzed what delegation is in “What is Delegation – A Swift...

This blog entry was inspired by Objc.io’s snippet titled “Enums instead of Booleans”. I really loved the clarity that using enumerations brought to even the simplest of examples that was presented in that snippet. If you haven’t seen it, check it out before continuing on! Objc.io’s snippet focused p...

My daughter, whom we codenamed Firefly, made her debut at 2:59 AM this morning! Being the nerd that I am, I built a small iOS app to reveal her name. Introducing….

Of the major design patterns that are prevalent in iOS development, delegation is one that appears quite often. For many developers entering app development for the iOS platform, dealing with delegates is a new concept. It certainly was for me. In my analysis of NSNotificationCenter vs Delegation, I...

Updated on September 21, 2016 – Swift 3.0 Implementing “pull to refresh” is a common need that arises when working with table views. There are typically two scenarios that folks find themselves in when attempting to implement this feature: They’re working with a UITableViewController They’re working...

There are times when it feels paralyzing to write tests first before any production code is written. Even with good requirements documentation, I often find myself asking, “How am I supposed to write a test to verify x about some thing that doesn’t exist in actual code yet?” It can be crippling. The...

The combination of an NSFetchedResultsController and a UITableView provides a powerful way to integrate Core Data with a user interface. The greatest benefits of using NSFetchedResultsController come when we use it to automatically update a table view when objects are added, updated, or removed from...