Why opaque return types are so important
In the full episode…
- Protocols aren’t enough
- Why not just use a concrete type?
- How this applies to SwiftUI
- Why does this matter?
- Challenges
Why subscribe?
Hacking with Swift+ delivers high-quality tutorials for subscribers, with each tutorial coming as a 4K Ultra HD video and in text form so you can read or watch – whatever works best for you.
So, you can get this full video and article as well as all other subscriber-only tutorials and all future tutorials – all by subscribing to Hacking with Swift+ today.
More from Hacking with Swift+
ADVANCED SWIFT
FREE: How to use phantom types in Swift
Phantom types are a powerful way to give the Swift compiler extra information about our code so that it can stop us from making mistakes. In this article I’m going to explain how they work and why you’d want them, as well as providing lots of hands-on examples you can try.
HIGH-PERFORMANCE APPS
FREE: Using memoization to speed up slow functions
In this article you’ll learn how memoization can dramatically boost the performance of slow functions, and how easy Swift makes it thanks to its generics and closures.
CUSTOM SWIFTUI COMPONENTS
FREE: Creating a WaveView to draw smooth waveforms
In this article I’m going to walk you through building a WaveView with SwiftUI, allowing us to create beautiful waveform-like effects to bring your user interface to life.
NETWORKING
User-friendly network access
Anyone can write Swift code to fetch network data, but much harder is knowing how to write code to do it respectfully. In this article we’ll look at building a considerate network stack, taking into account the user’s connection, preferences, and more.
ADVANCED SWIFT
Existentials and type erasure – part 1
Type erasure helps us solve difficult type system problems by purposefully discarding some information. In this article we’ll look at what the underlying problem is and how Swift solves it, and in the second part we’ll continue on to look at how we can build type erasure ourselves.
REMAKING APPS
Remaking the Tips app
In this article we’re going to look at how to rebuild the Tips app using SwiftUI, including how to make scrolling tabs of content, how to get a parallax scrolling effect, and more.
MAKING THE MOST OF FOUNDATION
Handling names correctly
There are lots of UI mistakes we can make in programming, but unless our bugs actually get in the way of functionality most users don’t care that much. But there is one exception, and we’re going to look at it here: in this article I’ll show you how to handle names correctly – the most personal data of all.
CUSTOM SWIFTUI COMPONENTS
Creating a FlipView to provide a card flip effect
If you’re looking for a simple and fun special effect to add to your code, I’ve got just the thing for you. In this article I’m going to walk you through building a FlipView with SwiftUI, which will encapsulate how to move between a front view and a back view using a 3D flip animation.
CUSTOM SWIFTUI COMPONENTS
Building a RadialMenu that shows many buttons around it
Sometimes pressing a button needs to present more buttons, and although you can use an action sheet for this it’s not ideal because it appears in a different location. In this article I’ll show you how to build a radial menu, which solves the problem by presenting a ring of buttons close to the user’s touch.
CUSTOM SWIFTUI COMPONENTS
Creating a RemoteImage to load images from the web
Just like UIKit before it, SwiftUI doesn’t come with built-in support for loading remote images, which makes it hard to get data from the internet. In this article I’ll show you how you can build a custom view that can fetch image from the internet, while also showing other images for different states.
CUSTOM SWIFTUI COMPONENTS
Creating a ShapeView to render UIBezierPaths
Bezier paths let us draw all sorts of shapes efficiently and smoothly, and with a little work we can bring them into SwiftUI then animate them smooth, and in this article I’m going to walk you through making a very simple ShapeView struct to do just that.
CUSTOM SWIFTUI COMPONENTS
Creating a StretchingHeader that sticks to the top of a view
When users scroll beyond the top of a scroll view the default behavior is to show some empty space, but many apps prefer to show a stretchy header area instead. In this article I’ll show you how to build that SwiftUI, making an image that stays fixed to the top no matter what.
ADVANCED SWIFT
The pros and cons of operator overloading
I’ve written about operator overloading previously, not least in my book Pro Swift, but in the article I want to go into more depth on the places where it’s really useful – and the places where it’s not such a good idea.
MAKING THE MOST OF FOUNDATION
Converting measurements safely
Apple’s Foundation framework makes it easy for us to convert any kind of measurement into any other kind of measurement. In this article I’ll show you how to make the most of these APIs, but also why it’s so useful that they work with Swift features such as operator overloading, plus important protocols such as Comparable, Equatable, and Codable.
CUSTOM SWIFTUI COMPONENTS
Creating an AccessibleStack that flips stack axis based on Dynamic Type
There are several times when you might want to flip between a HStack and VStack, but one useful option is to look at the Dynamic Type size. Apple uses this itself to switch list rows to a vertical layout when using larger fonts, and in this tutorial I’ll show you how it’s done.
INTERMEDIATE SWIFT
Understanding generics – part 1
Generics are one of the most powerful features of Swift, allowing us to write code once and reuse it in many ways. In this article we’ll explore how they work, why adding constraints actually helps us write more code, and how generics help solve one of the biggest problems in Swift.
INTERMEDIATE SWIFT
Creating a spaceship operator
When it comes to learning operator overloading, there is one operator that Swift lacks, that many other languages have, and is genuinely useful. In this article I’ll show you how to build the spaceship operator in Swift – it’s surprisingly easy, and useful too.
REMAKING APPS
Remaking the iOS lock screen
In this article we’re going to look at how easy it is to rebuild the iOS lock screen. Yes, this isn’t hard, but along the way I think you’ll pick up a few cool SwiftUI tricks, including better date formatting, haptic buttons, and more.
INTERMEDIATE SWIFTUI
Basic button customization using ButtonStyle
SwiftUI’s humble Button view is actually capable of doing remarkable things if you take the time to customize it. In this video I’ll be walking you through the ButtonStyle protocol, showing you how we can use it to make great-looking and reusable button effects.
DATA STRUCTURES
Linked lists
If there’s one data structure they just love teaching you at school, it’s linked lists. In this article we’re going to look at why linked lists are so appealing, walk through how to build a linked list with Swift, and look at an alternative approach using enums.