WWDC 2020 Expectations

Everyone has their own expectations when WWDC comes around. Here is what I’d like to see come from Apple and their various platforms.

SwiftUI improvements

Whether they call it SwiftUI 2, or just say they’ve made it better, I fully expect to see a “What’s New in SwiftUI” session this year, including some much needed additions. Of those, I’m hoping to see:

  • First party support for two-dimensional data grids. If List is to UITableView, then I want whatever is the equivalent of UICollectionView. There are a few interesting third-party solutions out there, and I’m not against using them, but I feel something like this would benefit from being provided by Apple themselves.
  • Fixed TabView. Right now, while you can easily create tabbed navigation, the SwiftUI TabView doesn’t behave like a normal UITabViewController. Specifically, if you navigate to another tab and come back, it’s up to the developer to maintain the hierarchy. So if I’m 3 views deep in tab 1, go to tab 2, then go back to tab 1, I’m back at the root by default.
  • Fixed NavigationView. This is more-so when it comes to master/detail on iPad. If I navigate a layer deep in a detail, then rotate the iPad, it resets the detail view while retaining the navigation stack. So I can push a view, rotate, push again, rotate, push again, and end up with what seems to be a navigation stack three or four views deep when in reality my hierarchy is just one or two.

What I do not expect to see is a complete replacement of everything available in UIKit or AppKit. What I mean: I don’t think we’ll see SwiftUI versions of WKWebView, MKMapView, or similar views. The current SwiftUI<->UIKit/AppKit functionality seems to cover situations like this.

“Swifty” Core Data

In Swift 3, Swift gained a huge improvement when it came to JSON Serialization: Codable. Codable is really two protocols: Encodable and Decodable. But together, they take the concept of serializing data, such as to/from JSON, and made is super easy to support.

I would love to see something similar done with Swift classes and Core Data. Could we make a data model conform for Core Data storage by just adding a protocol conformance? If that were possible, I know I’d love to use it.

I’d also hope that any such improvements would allow us to make a Core Data managed object that automatically conformed to Codable without requiring a custom init/decoder.

A Gamer’s GameCenter

I think GameCenter was one of Apple’s squandered opportunities. They offer a powerful Apple TV box that, if powered by newer iOS chipsets, can rival console performance. Yet they have nothing on their platform that resembles the social interactions and networking like you’d see on Xbox or Playstation. I keep hoping they’ll wisen up, revive that platform, and provide a better way for people to find their friends and game together.

An Improved Development Experience on iPad

Swift Playgrounds shows that it’s possible to do coding on the iPad. I’d like to see this turned up a notch, even if it isn’t a full-blown Xcode for iPad. With SwiftUI, perhaps we’ll see some middle-ground. Use your iPad to develop a SwiftUI app? Great. Want to integrate legacy components? Take your project to your Mac.

Even if that doesn’t happen, I’m curious to see what new features and enhancements come to the Swift Playgrounds app this year.

I’m sure that, with whatever Apple announces, I’ll be eager to install the latest betas and try things out. Even if none of my expectations are meant, I’m going to enjoy WWDC 2020.

iPhone SE performance versus Android Flagships

Jerry Hildenbrand at AndroidCentral:

Apple has updated the little iPhone SE for 2020, and even an Android fan has to see that it’s a great phone at an even greater price of $399 for the base model. It’s essentially an iPhone 8 with one big difference: it has Apple’s A13 Bionic chip buried inside. And that’s a big deal for a number of reasons.

I expect that some people are going to tell me about single thread versus multi-threaded performance and how the A13 GPU isn’t that great or how iPhones have much lower resolution screens so the chips don’t have to work as hard. All this is true, but another thing is true: the A13 is a stronger chip than the Snapdragon 865 for daily use in every category — we’ve seen this applied in real life in the iPhone 11 already.

Jerry does a nice job summarizing the performance of the A13 Bionic in the iPhone SE against the Snapdragon 865 found in many Android flagship phones. While it’s not been a specs game for many years, in terms of raw specs, the iPhone SE outperforms top-of-the-line Android phones at a third to a half of the price.

What sounds less crazy, and great to consumers, is that by using the A13 Apple can support the iPhone SE for years — and this phone will outlive the iPhone 8 it is slated to replace for a handful of extrayears because of the new chip. Basically, if the iPhone 11 can get updated, so can the iPhone SE. This is cool to hear today, but it will be really important in three years when another version of iOS is released and your $399 iPhone gets it on day one.

Android devices, typically, still get less than 3 years of updates. And it can take months between the time a new version of Android is released and it is made available on supported devices. And many devices, especially lower priced ones, may barely see one major software update.

And yet, the $399 iPhone SE is likely to get 5 years of major software updates, including new features.

John Gruber, at Daring Fireball:

And on the flip side, what do you get for $400 in Androidtown? Amazon sells the Motorola Moto Z4 for $500. Let’s just spot the Android side $100. The Moto Z4’s single-threaded Geekbench 5 score is about 500. That falls short of an iPhone 6S, a phone from 2015.

For the same price, you can buy an Android that performs about as well as a 5 year old iPhone. An iPhone that still supports the latest version of iOS.

Where are the popular Android phones from 2015 now?

  • Samsung Galaxy S6 – Last software update was 2016’s Android 7 Nougat, made available in 2017, with the last security patch in September 2018.
  • Sony Xperia Z5 Compact – Latest supported version is 2016’s Android Nougat.
  • Google Nexus 6P – Google’s flagship for the year, it got its last update at the end of 2017 with Android 8.0 Oreo.
  • Samsung Galaxy Note 5 – Last update, Android 7 Nougat, in 2017

It’s pretty clear to see: If you need a phone on a modest budget, the iPhone SE is the smartest choice. Best performance with the longest support means you’ll get the most for your money.

Appearance: Not Another Swift Podcast #16

This week, I joined Matt and Jason on their show, Not Another Swift Podcast. As usual, Matt is discussing his journey as he learns iOS development. This week we discussed project 16 of 100 Days of Swift. It was a chance to talk a little bit about MapKit, a framework I remember really enjoying when I worked with it over a year ago. I also got to open the show with a dad joke. How often can you say that?

It’s been years since I’ve been on a podcast, and it was great to be ‘back on the air’.

Using a Binding in SwiftUI – Simple Example

In my original post on Bindings in SwiftUI, I had mentioned when we might want to use a binding:

You would use a binding to create a two-way connection between a property that stores data, and a view that displays and changes the data.

I showed an example of how we could bind one of our local @State properties to a Toggle. The Toggle could update the state of our property through it.

We can use other system controls, such as TextField or Picker, to also update our local variables. But what if we want to have another one of our views update a variable owned by another? Let’s solve a simple example and, in doing so, we’ll see when we will make use of @Binding.

I have a simple view that displays my name. I am storing it locally as a variable.

struct NameDisplayView: View {
    var name: String = "unknown"
    var body: some View {
        Text("Your name is \(name)")

It simply takes the text there and outputs "Your name is unknown". It works, but I want to be able to update that name so I can have it show me and not assume I have no name.

Well, we know how we can bind to something from our original post. So let’s make a view where we can change some text.

struct NameChangeView: View {
    @State var text: String
    var body: some View {
        TextField("Type Here", text: $text)

So far, this is a simple example. If we loaded up NameChangeView, we could tap into the TextField and, as we type, text would be updated. Why? Because we have it bound to the text property on TextField, which is of type Binding<String>. So as the TextField updates the text, our view can get the latest values.

But let’s say we want to present this view as a sheet, let the user update the text, and then send it back to our original view. Can we do it? Yes!

What do we need to change so that our NameChangeView can pass changes back from itself to another view? All we have to do is change @State to @Binding. With that change, we now have two way communication via that variable.

Let’s add a little styling and a way to dismiss the view. That gives us our final form:

struct NameChangeView: View {
    @Environment(\.presentationMode) var presentationMode
    @Binding var text: String
    var body: some View {
        TextField("Type Here", text: $text, onCommit: { self.presentationMode.wrappedValue.dismiss() })

Now, how can we use this in our original view?

We’ll add a button to trigger a sheet. This happens by binding a local Bool to the .sheet(isPresented:) modifier. Lastly, we add our NameChangeView as what is being presented modally as a sheet. We pass our local name variable as a binding to that view, so it becomes $name.

struct NameDisplayView: View {
    @State var name: String = "unknown"
    @State var showNameChange = false
    var body: some View {
        VStack {
            Text("Your name is \(name)")
            Button("Change") {
                self.showNameChange = true
        .sheet(isPresented: $showNameChange) {
            NameChangeView(text: self.$name)

Now, we can tap on “Change”, which will present our text field. We can tap on it, change our name, hit “Return”, and be taken back to our original view but with our name in place.

Bindings might seem like a new concept to iOS developers, but they open up a lot of possibilities in Swift. Explore various ways that you can use bindings to communicate between views. You’ll find them very useful, especially in cases of user input as we saw in our example.

You can find the example code in this Github Gist.

‘Frolicking around in excess’

Matt Birchler, writing about what matters in a phone:

So when I see the $399 iPhone SE with 5 years of likely updates, with a really good single lens camera, and with it’s processor that’s faster than all 2020 $1,000+ Android phones, and will likely still be faster than all 2021 Android phones…well, it just looks like a good phone, and it makes it look like we’ve been frolicking around in excess for years now.

I’m one of those people with an iPhone 11 Pro. I enjoy Face ID. I like the ways I can interact with my phone without a home button. I like the triple camera system. I don’t regret owning it. But I also know it’s not for everyone.

For everyone else, people that are just looking for the best deal on a smartphone in general, Matt hits it right on the head: The new iPhone SE is likely the best purchase you can make right now. Maybe even the best purchase next year.

Bindings in SwiftUI

Property wrappers were one of the recent additions to Swift. SwiftUI makes use of several very useful property wrappers. One of them is @Binding. The @Binding property wrapper is really just a convenience for the Binding<T> type.

But before we go into using bindings, what are bindings?

Per Apple’s documentation, a binding connects a property to a source of truth stored elsewhere, instead of storing data directly. You would use a binding to create a two-way connection between a property that stores data, and a view that displays and changes the data.

In SwiftUI, you’ll find this to be a fairly common pattern, especially with built in input fields.

Binding Example

Let’s say we want a view with a switch for the user to interact with. How do we build it?

struct BindingExample: View {
    @State var switchIsOn = false

    var body: some View {
        Form {
            Toggle(isOn: $switchIsOn) {
                Text("Switch 1")

First, we need a mutable variable to hold the state of our switch. In this case, we have a Bool, named switchIsOn. We have to use the @State wrapper so it can be modified in our view.

Next, when we build our Toggle, we need to provide a binding to a property that will hold the state of the toggle. When we pass in the variable, we use the dollar sign to denote that we’re binding to it. So our view holds the current state of switchIsOn, while the Toggle has a binding internally. When the state of the Toggle flips, it is propagated through $switchIsOn back into our view.

Creating a manual binding

If we again look at Apple’s description of a binding, we see that it involves a two-way connection. The binding needs to know the value to get, and where to set the new value when it is changed.

With that knowledge, we can look at how Binding workings. Let’s look at our example again. This time, we’re going to make a binding ourselves.

struct BindingExample: View {
    @State var switchIsOn = false 

    var body: some View {
        Form {  
            Toggle(isOn: Binding(get: {
            }, set: { newValue in
                self.switchIsOn = newValue
            }) ) {
                Text("Also Switch 1")

Binding has an initializer that takes a couple of arguments. One, with the get label, is a closure explaining where the binding gets its value. In our example, this is our switchIsOn variable. The other, set, is given the new value for the binding. This gives us the opportunity to do something with it now that it has changed. In our case, we’re setting switchIsOn to the new value.

In its most basic form, Binding opens up a lot of interesting possibilities. In later posts, I’ll talk about when we might want to create a binding between our views, as well as some interesting problems a manual binding can solve.

Portrait Mode and the Neural Engine on iPhone SE

Apple finally announced the successor to the iPhone SE. Also called the iPhone SE (and from here, the one I am referring to with that name), it built on the expectations that many were thinking: A reuse of an existing design with newer internals. This is exactly how Apple approached the first SE model. So it made since that the new iPhone SE followed suit.

Design wise, the iPhone SE is identical to the iPhone 8 that it replaced. But internally, it contains a lot of technology found in the iPhone 11: A13 Bionic chip with the third generation Neural Engine, support for WiFi 6, Gigabit class LTE, etc. It also made some changes from the iPhone 8 in line with the iPhone 11, such as the removal of 3D Touch.

But there are some camera differences with the iPhone SE, especially when compared to the iPhone 8, that made me really think.

Portrait Mode

The iPhone SE, like the visually identical iPhone 8, has a single camera on the back side. If you compare the specs between the iPhone 8 and iPhone SE, you’ll see no difference:

  • Single 12MP Wide camera
  • Wide: ƒ/1.8 aperture
  • Optical image stabilization
  • Digital zoom up to 5x
  • True Tone flash with Slow Sync

The iPhone 8 camera was really good, so keeping that same sensor, especially to reduce cost, makes sense.

But there’s something the iPhone SE has than its predecessor didn’t have:

  • Portrait mode with advanced bokeh and Depth Control
  • Portrait Lighting with six effects (Natural, Studio, Contour, Stage, Stage Mono, High‑Key Mono)

The iPhone SE adds Portrait mode, something that initially came to the iPhone 7 Plus because of its dual cameras. Bringing this to a 4.7-inch iPhone like the iPhone SE is a first.

Now, this isn’t the first time a single camera iPhone has received Portrait Mode. The iPhone XR, released in 2018, had a single backside camera and supported Portrait Mode. If we compare the stats of the XR’s backside camera against the iPhone 8 and iPhone SE, we’ll see that it’s identical. However, there is a notable difference with the iPhone XR:

  • Portrait Lighting with three effects (Natural, Studio, Contour)

The iPhone XR only supports three effects in Portrait Mode on the single backside camera. What gives?

Apple explains in their press release:

iPhone SE features the best single-camera system ever in an iPhone with a 12-megapixel f/1.8 aperture Wide camera, and uses the image signal processor and Neural Engine of A13 Bionic to unlock even more benefits of computational photography, including Portrait mode, all six Portrait Lighting effects and Depth Control.

The neural engine in the A13 is able to do much better with the single camera sensor input to process all of the available effects for Portrait Mode. So much so that it enables all six effects on the single camera!

But it doesn’t stop there!

A First on an iPhone

Let’s compare the front camera on the iPhone 8, iPhone XR, and iPhone SE.

The iPhone 8 and iPhone SE both have identical specs:

  • FaceTime HD camera
  • 7MP photos
  • ƒ/2.2 aperture
  • Retina Flash
  • Auto HDR for photos
  • 1080p HD video recording at 30 fps

Since it doesn’t include the TrueDepth camera system, which uses a camera and additional sensors to detect facial features and depth, the iPhone SE has Touch ID instead of Face ID for unlocking the device. It also makes sense that it doesn’t have Portrait Mode on the front camera.

Except it does.

  • Portrait mode with advanced bokeh and Depth Control
  • Portrait Lighting with six effects (Natural, Studio, Contour, Stage, Stage Mono, High‑Key Mono)

Again, from Apple’s press release, just after the earlier quote:

Using machine learning and monocular depth estimation, iPhone SE also takes stunning Portraits with the front camera.

The iPhone SE is the first iPhone without the TrueDepth camera system with front facing Portrait Mode. It’s using a single camera, like the backside, to enable the same level of Portrait Mode, using the same cameras as found in the iPhone 8.

It’s amazing what the A13 Bionic chip is able to enable. It and the third generation Neural Engine definition power the most powerful smartphones in the world. In the words of Apple SVP Phil Schiller: “It’s a big deal.” And to be able to include their fastest chip in their cheapest iPhone? An easy win for Apple.

Property Wrappers in Swift

With Swift 5.1 and Xcode 11, many new features came to Swift. A lot of these were built in to help enable SwiftUI in Apple’s latest OS releases. While diving into SwiftUI is a great way to understand those features, there are some that we don’t need to go into SwiftUI to understand. One of these is property wrappers.

I like to explain property wrappers by a literal definition of the phrase: They wrap properties in functionality. While there are some built into various Apple frameworks (ie SwiftUI), it’s easy to create your own, and they can give you a lot of neat functionality.

How to create a property wrapper

To define a property wrapper, you need to have a custom type (I typically use structs) that you mark as a property wrapper with the @propertyWrapper keyword.

struct Wrapper { 


By adding that attribute, my type now must conform to its requirements. To do so, I need to add a non-static property named wrappedValue. The type of this property will depend on the kind of wrapper you are building. Let’s look at some practical examples and see what we can build.

Easily decoding an ISO 8601 Date

Since Swift 3, we’ve had the very convenient Encodable and Decodable protocols. The type alias Codable is how we typically see it. Having our models conform to Codable allows us to easily encode and decode our models to and from JSON for API communication.

The Date type conforms to Codable. But how does it encode/decode by default?

struct DateTest: Codable {
    var date: Date = Date()

let dateTest = DateTest()
let data = try JSONEncoder().encode(dateTest)
let json = try JSONSerialization.jsonObject(with: data, options: [])

// {
//    date = "608081487.019236";
// }

Okay. At least Date can encode automatically. I can live with that. But it looks like it’s turning a date into a number. What if we want to work with different standard, such as an ISO 8601 Date?

What is an ISO 8601 Date? It a popular date format presented as a string where a date like 10:43 pm on April 4, 2020 would appear like this:

So can Date decode this by default? Let’s find out!

let isodateJSON = """
    "date": "2012-07-14T01:00:00+01:00"

let isoDecodeTest = try JSONDecoder().decode(DateTest.self, from: isodateJSON.data(using: .utf8)!)

So using a multi-line statement in Swift, I’m going to try and decode an instance of our DateTest struct with this JSON object. Will this work? If you saw how Date encoded itself, then you won’t be surprised by the response we get from trying to decode this JSON.

ERROR: typeMismatch(Swift.Double, 
    Swift.DecodingError.Context(codingPath: [CodingKeys(stringValue: "date", intValue: nil)], 
    debugDescription: "Expected to decode Double but found a string/data instead.", 
    underlyingError: nil))

While we have a valid date format, Date is expecting a Double. What can we do?

We could create a custom JSONDecoder when decoding our type. But if we want to support ISO 8601 dates across various models, then we have to create custom decoders for all of them. That could end up being a lot of manual decoding work. OR… we could create a property wrapper to automatically decode the string coming from our JSON into a valid Date.

We start by creating our property wrapper. Ultimately, we want to provide a Date. So that will be our wrapped type.

struct ISO8601Date {
    var wrappedValue: Date

This satisfies the basic requirements of @propertyWrapper. Now we have to add our own functionality. In our case, here is where we will build our custom encoding and decoding capabilities.

We start by declaring ISO8601Date itself as conforming to Codable. This will let us wrap properties in a Codable-conforming model and not cause any errors about a model needing to manually provide such conformance.

Next, we create our custom Codable conformance within our ISO8601Date struct.

init(from decoder: Decoder) throws {
    let value = try decoder.singleValueContainer()
    let stringValue = try value.decode(String.self)
    if let date = ISO8601DateFormatter().date(from: stringValue) {
        wrappedValue = date
    } else {
        throw DecodingError.typeMismatch(Date.self, DecodingError.Context(codingPath: [], 
                        debugDescription: "Failed to decode ISO Date. Invalid string format."))

func encode(to encoder: Encoder) throws {
    var container = encoder.singleValueContainer()
    let string = ISO8601DateFormatter().string(from: wrappedValue)
    try container.encode(string)

Our initializer will try and decode a string. If this string can be used to decode a date in the ISO 8601 standard format, it will do so. Otherwise, it will throw an error. Meanwhile, our custom encode function takes the stored date and encodes it into a string using the ISO8601DateFormatter.

Lastly, we add a simple init to allow the user to set a default value with our property wrapper.

init(wrappedValue: Date) {
    self.wrappedValue = wrappedValue

Put all of this together and what do we get? If we look at our original DateTest model, we can now prepend the @ISO8601Date attribute to our date property and it will encode to and decode from an ISO 8601 string automatically.

struct DateTest: Codable {
    @ISO8601Date var date: Date = Date()

Using UserDefaults for property storage

You may be using UserDefaults in your app to store simple properties. Perhaps it’s a Bool saying if a user has enabled or disabled some feature. Or perhaps you’re storing a String of the last logged in user. You may have built convenience properties to read and write these values. In doing so, you may have ended up with a pattern like this:

class SettingManager {
    static var userViewedWhatsNew: Bool {
        get {
            UserDefaults.standard.bool(forKey: "userViewedWhatsNew")
        set {
            UserDefaults.standard.set(newValue, forKey: "userViewedWhatsNew")
    static var lastLoggedInUser: String? {
        get {
            UserDefaults.standard.string(forKey: "lastLoggedInUser")
        set {
            UserDefaults.standard.set(newValue, forKey: "lastLoggedInUser")

There’s nothing wrong with the above code (except maybe hard-coded key values). But as you add support for more and more properties, things get to be real tedious. So if we were to abstract this out, what pattern do we see?

For each property, we are both (a) getting the value from UserDefaults and (b) setting the value to UserDefaults using the same (c) key. With this pattern in mind, let’s approach our property wrapper.

struct UserDefault<StoredType> {
    public let key: String

    var wrappedValue: StoredType {
        get {
            UserDefaults.standard.object(forKey: key) as! StoredType
        set {
            UserDefaults.standard.set(newValue, forKey: key)

Instead of using wrappedValue to store a value we initialize, like in our first example, we have a computed getter and setter. It is performing our reading and writing with UserDefaults. The key used for those transactions? We provide it in our property wrapper.

What data type does this work with? You’ll see that we are using a generic type (StoredType). It will inherit the type from whatever you end up wrapping.

But wait! What if you wrap an optional type, like String?. Won’t the getter crash if there is no object for key? Nope! Because it’s coming back as an optional, or Optional.none case (if you look at how Optionals work in Swift), which is a valid value for something of type String?. But if we did try to read a String that wasn’t there, then it would crash.

So how about we add a default value?

struct UserDefault<StoredType> {
    public let key: String
    public let defaultValue: StoredType

    var wrappedValue: StoredType {
        get {
            UserDefaults.standard.object(forKey: key) as? StoredType ?? defaultValue
        set {
            UserDefaults.standard.set(newValue, forKey: key)

Now we will attempt to return a value of type StoredType from UserDefaults but, in the event no such object exists, we will return our defaultValue.

How can we use this in our SettingManager above?

class SettingManager {
    @UserDefault(key: "userViewedWhatsNew", defaultValue: false) 
    static var userViewedWhatsNew: Bool    

    @UserDefault(key: "lastLoggedInUser", defaultValue: nil) 
    static var lastLoggedInUser: String?

If we were to add support for a new property stored in UserDefaults, it is super simple.

Now, notice how we are setting the key and defaultValue properties when declaring our property wrapper. This is making use of the synthesized initializer on our struct. You could make your own init function and use it when declaring the property wrapper.


Property wrappers are super helpful. They can help you take repeated code and patterns away from your properties and move them into a reusable component. As we’ve seen here, you can make various Codable edge cases easy to solve. They can also help you with code you find yourself repeating in things like a set, didSet, or other such case.

Like other Swift features, property wrappers are just another tool that are worth having in your developer tool box. I hope this post helped demystify them a little bit and make them more approachable for you.

You can find the code for this post in this Github Gist.

Swift Protocols Aren’t Scary

For people new to Swift, or coding in general, there are some keywords that might seem daunting. Optionals. Generics. Sometimes you can explain these in a simple way. Other times, exposure to them might scare learners.

Protocols might seem like a big concept for some. If you look at how many protocols exist in various frameworks, you might think, “Wow, that’s a lot to learn! When will I use all of these?”

For instance, the Int type conforms to 11 different protocols. Do you need to know them all?

What is a protocol?

A protocol is essentially a blueprint. It defines functionality. This can be requiring the existing of certain properties or functions. Something that conforms to a protocol is required to provide the required elements.

For instance, I could declare a protocol that requires the conforming object, whether a class, struct, or enum, to have a name property.

protocol Nameable {
    var name: String { get set }

If I have a struct representing, say, an instrument, I can have it conform to that protocol, which will require the presence of a name property.

struct Guitar: Nameable {
    var type: String
    var name: String // Required because of protocol

Protocol conformance can be declared when you create your type, or it can be done in an extension. However, extensions cannot contain stored properties, so you can only add support for required functions in extensions.

protocol DataSource {
    func numberOfItems(in section: Int) -> Int
    func dataToShow(at indexPath: IndexPath) -> Data

class DataManager {
    // Your class stuff here

extension DataManager: DataSource {
    func numberOfItems(in section: Int) -> Int {
        // Return the number of items in each section
    func dataToShow(at indexPath: IndexPath) -> Data {
        // Return some data to show for each row/section

When would I use one?

You would use a protocol when you want to require functionality for a type. When would you use this?

With the exception of very basic iOS applications, you are likely to come across a protocol and not even realize it. Consider the following example:

class MyTableViewController: UIViewController {
    var tableView: UITableView!
    override func viewDidLoad() {
        tableView.dataSource = self
        tableView.delegate = self

Here, we have a view controller that we’ve created. It has a table view in it. To have a working table view, we need to have a data source and delegate. In simple examples, you would see what we have here: the class itself conforms as a datasource and delegate.

To do that, we’d have to have our class conform to 2 different protocols. One tells the requirements for the data source, the other tells the requirements to be a delegate.

extension MyTableViewController: UITableViewDataSource {
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        // Return number of rows in each section
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        // Return the table view cell for each part of the table view

extension MyTableViewController: UITableViewDelegate {
    // Add support for the delegate methods you want to support

So here, we’ve told our class to conform to two protocols so that it can satisfy the requirements of the table view.

They’re just blueprints

When we look at the above example of the UITableView, when it’s looking for something to be a data source, it’s wanting something that conforms to UITableViewDataSource. It’s basically saying, “If you conform to these blueprints, you, too, can be a data source!”

Don’t look at the presence of ALL protocols available to use as daunting. Remember: it’s just saying there are dozens of blueprint options out there. But they’re only used for specific reasons. UITableView wants its data source to conform to a certain protocol. UIScrollView’s delegate has certain requirements.

And what about what you might make? Would you ever want to make a protocol? Sure. If you ever want to require your types have certain properties or functions, you would create your own protocol. You’d basically be drafting your own blueprints in Swift.

That’s all protocols are. Blueprints. They’re not scary at all.

iPhone SE 2 Expectations

For months, rumors have circulated that Apple is doing another iPhone SE. But what is Apple’s goal with it? What can we reasonably expect, and why?

Is It Size?

Some think the SE 2 (or whatever it will be called; more on that later) is Apple’s chance to release another smaller phone into the line up. While it does give them the opportunity, that doesn’t seem like the role the SE 2 is to play. The reason for that is because that wasn’t the primary goal of the first SE.

Let’s look back at the original iPhone SE. It launched in the spring of 2016, roughly six months after the release of the iPhone 6S. When the iPhone 6S launched, the iPhone 5S, a then 2 year old phone, was the most affordable option, coming in around $449. The SE ended up replacing it, coming in at $399.

The SE retained the beloved 4-inch screen size that many loved. And while size made it an attractive purchase, there was another benefit. They were able to pack in the same features and specs of the iPhone 6S into the smaller design. But wait: didn’t it cost less than the iPhone 5s? How could they do that?


Being based on the older design, it makes sense that, after having manufactured the 5-series for a couple of years, the cost of building the SE, as well as R&D, had been recouped more than a new flagship. The tooling required to build most of the SE were thus already working as a well oiled machine. Savings were easily found there, which could result in a lower price.

The rumored iPhone SE 2 will be no different. It’s likely to look like an existing design (iPhone 8, I’d say), but with improved internals. Yes, that means a newer set of internal components had to be designed to fit into that enclosure. But the cost of producing that enclosure no doubt will allow for a low price.

The one “downside” to people owning such a phone: It won’t look as flash as the iPhone 11 Pro (or whatever phones are debuted later this year). But for the audience Apple is likely targeting with this phone, I don’t think they care so much about flashy. It’s about getting the most bang for your buck.

I know I would love to see another $399 iPhone with the latest specs, and I know many others would, too. Let’s see what happens after one is announced.