So, you want to get into iOS development? I was in your shoes on January 27, 2010, when Apple first announced the iPad. As soon as the conference was over, I knew that I wanted to learn how to create apps for the iPad. I signed up for the Apple Developer website and paid my $99 annual fee. But then, I realized that I did not know where to begin. A large variety of instructional books or videos did not exist, especially since the iPad hadn't released. I had previous programming experience; however, I had no idea how to write Objective-C (the original programming language for iOS). Therefore, I had to teach myself the basics. In this book, we will learn what it takes to become an iOS developer together.
If you are new to programming, take your time. You should understand the lessons that are provided in one chapter before moving on to the next. These essential skills will set you up with a solid foundation in iOS development. If you have previous programming experience, you should still review the earlier chapters, as they will be a refresher for you.
Throughout this book, we will work in Xcode, specifically Xcode 10 (and Swift 4, which we will tackle later in this book). Xcode is known as an Integrated Development Environment (IDE). Using Xcode gives us everything we will need to build apps for iOS, tvOS, macOS (formerly, OS X), and watchOS. In this chapter, we will explore Xcode to help you get more comfortable using it. If you are not on Xcode 10, make sure to update Xcode, as the code in this book will not run correctly otherwise.
Our focus in this book will be on creating a universal iOS app (an app for both the iPhone and iPad). The best way to do this is to create a project to familiarize yourself with where everything is and how to find what you need. So first, let's first download and install Xcode.
To download Xcode, launch the App Store on your Mac and then type Xcode into the search bar in the upper-right corner:
Next, click on INSTALL:
Once installed, launch Xcode, and you should see the following Welcome to Xcode screen:
If this is the first time you have launched Xcode, then you will see No Recent Projects in the right-hand panel. If you have previously created projects, then you will see those listed to the right. To get started, we are going to click on Create a new Xcode project in the left-hand panel of the welcome screen. You will see the new project screen, as follows:
Across the top of this screen, you can select one of the following items: iOS, watchOS, tvOS, macOS, and Cross-platform. Since we are creating apps for iOS, make sure that you have iOS selected. Then, choose Single View App and click on Next. Now, you will see an options screen for a new project:
This option screen has the following seven items to complete or choose:
- Product Name: The product name is your app. We are going to set ours as ExploringXcode.
- Team: The team connects to your Apple account. We are going to ignore this for now, because we do not need the Team for this chapter. If you already have a team set up, leave it as is. We will cover this in greater detail later in this book.
- Organization Name: You can set the organization name to your company name, or just use your name.
- Organizer Identifier: You will set the organizer identifier to be your domain name in reverse. For example, my website URL is cocoa.academy, and therefore, my identifier is academy.cocoa. Since URLs are unique, it will ensure that no one else will have your identifier. If you do not have a domain, then use your first and last names for now. However, you will eventually have to purchase a domain if you want to submit your app to the Apple Store.
- Bundle Identifier: When you create a new project, Apple will combine your Product Name with your Organizer Identifier to create your unique bundle identifier. So, even if 10,000 people create this project, each person will have a different bundle identifier.
- Language: Set language to Swift.
- Checkboxes: You can uncheck Use Core Data, Include Unit Tests, and Include UI Tests, as these are things that we will not use in this chapter.
Now, select Next, and Xcode will prompt us to save our project. I have a dedicated folder for all my projects, but you can save it on your desktop for easy access.
Your project is now open, and it is time for us to get familiar with all of the panels. If this is your first time in Xcode, then it will probably be a bit overwhelming for you. Therefore, we will break it down into six parts:
- NAVIGATOR PANEL
- STANDARD EDITOR
- UTILITIES PANEL
- DEBUG PANEL
- WINDOW PANE CONTROLS
The primary use of the navigator panel is to add new files and select existing files. The other icons are used from time to time; we will cover them as we need them.
The standard editor is a single panel view that's used to edit files. The standard editor area is the primary area in which you will work. In this area, we can view storyboard files, see our Swift files, or view our project settings.
The utilities panel can be a bit confusing when you first use Xcode because this menu changes based on what you have selected in the standard editor. When we start building an app, we will dig deeper into this. For now, know that the utilities panel is made up of the inspector pane at the top and the library pane at the bottom. The inspector pane allows you to change the attributes or properties of things you put in your storyboard; the library pane enables you to insert objects, image assets, and code snippets into your app.
The debug panel will allow us to see log messages from our app. You will become very familiar with this panel by the time you finish this book. The debug panel is one of the most excellent tools for getting feedback on what your app is doing or not doing.
Next, we look at the toolbar, which is demonstrated as follows:
First, we have a play button, which is how we launch our app (or use command + R). Next, you will see a stop button, which will not be active until you run your app. This stop button (or command + .) is used to stop your app from running. To the right of the stop button, you will see your target (your project name), along with the current simulator that has been selected. If you click on your project name, you will see a screen similar to this:
This drop-down menu, which we will call the Device and iOS Simulators drop-down menu, allows you to change your simulator type. For our project, select iPhone7 Plus as your simulator and then click on the play icon (or use command + R) to run your app.
Now, let's return to Xcode and select the stop button (or use command + .).
If you use the keyboard shortcut, make sure Xcode is in focus; otherwise, this shortcut will not work. I work on a 15-inch MacBook Pro Retina. Therefore, when I am working on an app, I will use the iPhone X or iPad Air 2 simulator in landscape mode. They both fit nicely on my screen without me having to resize either.
In addition to the Simulator, there is a Build Only Device as well as a Device section, both of which can be found at the top of the Device and Simulator drop-down menu that was shown earlier in this chapter. Note that, for our purposes, you will only need a simulator while we are building the app; however, you can add an iOS device if you would like (see under iOS Device).
The Generic iOS Device, under the Build Only Device section of the Device and Simulator drop-down menu, is used for when you need to archive your app, which means that you are preparing your app for submission to Apple (either to the App Store or Test Flight). If you try to select Generic iOS Device now and run the app, you will get the following message:
Therefore, change Generic iOS Device to an actual simulator, and then you will be able to continue.
If you do not have a device connected to the computer, you will see No devices connected under the Device section of the Device and Simulator drop-down menu.
As noted earlier, when we start building the Let's Eat app, you will have the option of using the simulator or connecting a device to Xcode. Using a device is slower; however, the simulator will not perform in the same way as a device will.
In the past, you needed to have a paid account to build your app on a device. Nowadays, you do not need a developer account to run the app on your device. Note that, if you decide to connect your device instead of using a simulator, you will need iOS 12 installed on it. Xcode 10 introduced the capability of connecting your phone wirelessly. We will look at the traditional way first and then we will go over how you can connect your phone wirelessly.
The following steps are only intended for those of you who do not want to pay for the Apple Developer Program at this time:
- Connect your iOS device via USB.
- In the drop-down menu, select your device (here, I have chosen Xclusive iPhone 6 Plus):
- Wait for Xcode 10 to finish indexing and processing. The indexing and processing may take a bit of time. Once complete, the status will say Ready.
- Run the project by hitting the Play button (or use command + R).
You will get two errors that state the following:
- Signing for ExploringXcode requires a development team.
Select a development team in the project editor.
- Code signing requires a product type application in SDK iOS 12.0.
- Signing for ExploringXcode requires a development team.
Ignore the specifics of these errors as they indicate that we need to create an account and add our device to that account.
- Now, in the standard editor, you will see under Signing that you need to add an account:
- Click on Add Account. If a Sign into Xcode with your Apple ID dialog box does not pop up, inside the Accounts screen on the bottom left, click on the + and select Apple ID:
- Then, when you click on Create Apple ID, you will be asked to enter your birth date, name, email, and password, along with a number of security questions. Make sure that you verify your email before you answer the security questions, otherwise you will have to come back to this screen and add your Apple ID again.
- Once you have finished all of the steps, you will see your account, as follows:
If you already have an account, then instead of seeing Add Account, you will see a drop-down menu with your account listed. If your device is not connected to this account, you might see a message asking if you would like to add your device to your account. Adding your device to an account is for testing purposes only.
Now that you have your phone and account connected, you can quickly get your phone set up to run wirelessly. With your device already connected via USB, go to Window | Devices, and then Simulators. Click on the checkbox marked Connect via network:
Make sure that your phone and your computer are connected to the same Wi-Fi network.
When I first connected to my device, I saw a globe icon in Xcode that lets you know that your device is connected via the network, as demonstrated in the following screenshot:
After a short time, the globe went away. Even if you do not see the icon, you can disconnect the USB, and your device should still be connected to Xcode (as long as it is connected to the same Wi-Fi network).
You will not need to use a device for this book, but it is always good to run your app in an actual device before you submit it to the store.
Before we get to the right-hand side of the toolbar, select the Main.storyboard file in your navigator panel. This file is used to display all of your visual setup for your entire app. We will this in detail later in this book. After you select the file, you should see the following:
The following screenshot shows the window pane controls:
Moving on to the window pane controls, you will see two groups of icons. The first group is called the Editor Mode, and the second group is called the View. Let's look at the functions of the Editor Mode icons:
|Editor Mode icons
|This icon controls the standard editor (which is the center panel in the earlier screenshot of the Main.storyboard file in the navigator panel).
|This icon splits the Standard editor into two panels, where you will see the ViewController.swift file on the right. We will use this split screen throughout this book.
|This icon is the Version editor. We will not address the Version editor in this book since it is a more advanced feature.
At this point, you might be thinking that there are way too many panels open, and I would agree with you! The last panel is where the previous group of View icons in the toolbar comes in handy.
Let's look at these icons and their functions in the following table:
|View Mode icons
|This icon will toggle (hide or show) the navigator panel (or use command + O).
This icon will toggle (hide or show) the debug panel (or use command + shift + Y).
This icon will toggle (hide or show) the utilities panel (or use command + alt + O).
Congratulations! You have finished exploring the basics of Xcode. When we start building our app, we will cover the more essential parts of Xcode in depth. In the next few chapters, we will begin learning about the Swift programming language. We will use the latest Swift version, and this will be a basic intro into the programming language. If you are familiar with Swift, feel free to skip ahead to Chapter 6, Starting the UI Setup. Even if you are familiar with Swift, it is always good to go back through the basics as a refresher. So, let's get started!