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How Do Unwind Segues Work

Unwind segues, introduced in iOS 6, cause quite a bit of confusion among developers. Even if you are used to working with storyboards, you may have stayed clear from unwind segues because you don't exactly know what they are or how they work. This article resolves that problem. In this tutorial, I explain the nuts and bolts of unwind segues.

in Storyboards

How To Delete Every Record Of A Core Data Entity

A question I hear surprisingly often is how to remove every record of a Core Data entity. This is a valid question and it sounds trivial. Up until iOS 9 and OS X El Capitan, though, it wasn't that trivial at all. Because not every application requires iOS 9 or OS X El Capitan, I would like to start this tutorial by explaining how to solve the problem the old way.

in Core Data

How To Observe A Managed Object Context

Have you ever wondered how the NSFetchedResultsController class does its magic? A fetched results controller seems to be magically notified whenever the result of its fetch request changes. The Core Data framework exposes several APIs that allow developers to replicate the behavior of the NSFetchedResultsController class.

in Core Data

Dissecting Auto Layout Constraints

If you plan to build an iOS application that look great on any device, then Auto Layout is your only viable option. The user interface of modern iOS applications is driven by Auto Layout and Apple continues to improve and invest in Auto Layout with every iteration of the platform.

in Auto Layout

What Is Auto Layout

Before discussing the benefits of Auto Layout, we need to take a moment to discuss the options you have to create user interfaces on iOS.

in Auto Layout

Testing View Models With Model-View-Viewmodel

Model-View-Viewmodel And Swift

View controllers are notoriously hard to test. Ironically, the Model-View-Controller pattern forces developers to put a lot of the heart and brains of their applications in view controllers.

in Patterns

More Swift And Model-View-Viewmodel In Practice

Model-View-Viewmodel And Swift

In the previous tutorial, we laid the foundation for adopting the Model-View-ViewModel pattern in the profile view controller of Samsara. We already implemented the Time section of the table view. This tutorial continues with the Warm Up and Cool Down sections.

in Patterns

Swift and MVVM in Practice

Model-View-Viewmodel And Swift

Earlier this week, I wrote about the pros and cons of the Model-View-Controller pattern. In that article, I also made mention of a promising alternative pattern, Model-View-ViewModel.

in Patterns

Five Common Questions About Swift

Even though Swift may be reminiscent of several other programming languages, such as Ruby, Java, and JavaScript, it is dangerous to compare it with other languages. In this article, I answer five common questions about the Swift programming language.

in Swift

A Roadmap for Learning Core Data

Apple's persistence framework is sometimes said to have a bad reputation. Is that warranted? Is Core Data difficult to use? Does it have a steep learning curve? Is it a dated persistence solution?

in Core Data

What Is Wrong With Model-View-Controller

Model-View-Viewmodel And Swift

Model-View-Controller, or MVC for short, is a widely used design pattern for architecting software applications. Cocoa applications are centered around MVC and many of Apple's frameworks are impregnated by the pattern.

in Patterns

Is Core Data Thread Safe

Is Core Data thread safe? Yes and no. Even though the framework originated in a time where computers with multicore processors were rare, Core Data is designed to operate in a multithreaded environment. In other words, it works fine on the latest iPhone and a Mac Pro with 28 cores.

in Core Data