Starting to Integrate the Facebook SDK with an iOS app

Although you can work offline with Xcode as you develop an app, you cannot work offline to create apps for Facebook or iOS, because you need to interact with the Facebook and iOS environments. If you have anything other than an ordinary Internet connection (for example, if you are behind a firewall that limits the sites you can visit), check out the basic steps to get started to make certain that you don’t need permission from another part of the organization.

Start by creating an Xcode project to use for testing. In this chapter, the Single View sample app that is part of Xcode will be used. Figure 7-1 shows how you can create it.

Make a note of the app bundle identifier that is created based on the data you enter for the app . As you can see in Figure 7-2, the bundle identifier for this app is com.champlainarts.MySingleViewApp.

As always when you create a new app from a template in Xcode, run the app either on a device or on a simulator to make certain that it works properly. Figure 7-3 shows what you should see if you run it on the simulator for iPhone 8.

Yes, a successful implementation of the single-view app shows nothing. As you will see later in this chapter, you can easily add a label. All you should be concerned with at this point is that the app doesn’t fail or crash when you run it on Xcode .

Download the Facebook SDK for Swift

Log in to your developer account on developers.facebook.com. You’ll see choices to download the Facebook SDK for iOS, Android, and PHP, as well as for other platforms. As of this writing, the basic iOS SDK is still written in Objective-C, but you can download the Swift version if you want (you’ll see how to do that in this section).

The Swift version of the iOS SDK is under documentation. Once you’ve logged in, use the Docs menu item in the top navigation bar to get to the Documentation page, as shown in Figure 7-4.

You may have to scroll down, as you can see in Figure 7-5, to find the Swift SDK.

Once you have located the “SDK for Swift” link, open it, as you can see in Figure 7-6.

The frameworks shown in Figure 7-6 are the heart of the Facebook SDK for Swift. All frameworks for iOS were originally written in Objective-C. Today, some of the new frameworks are written in Swift, but when you build a Swift-based app, it is not a problem that some (or all) of the frameworks are written in Swift. Thus, when you download the SDK for Swift, you’ll wind up with frameworks that are often written in Objective-C, and that doesn’t matter. When you download the SDK for Swift, as shown in Figure 7-6, some of the frameworks have enhancements specifically for Swift, so keep these files safe and just add them as needed to your app.

The download link in Figure 7-6 takes you to GitHub, as you can see in Figure 7-7. You can download the source code as .zip or tar.gz.

The files downloaded from GitHub will vary over time both in content and in name. The downloaded files at the time of this book’s writing look like Figure 7-8.

Adding Frameworks and Functionality to Your Facebook App

You can work around the issue of what file is where by using CocoaPods, but if you prefer to work with the actual files themselves, one technique that works for many people on many projects is to look for a sample file or app. In this case, there’s a Samples folder containing a SwiftCatalog app. Many times (but not always!) the sample app will be updated for any given project before the documentation is updated. If that is the case, build the app. If you look at the project navigator, as you can see in Figure 7-9, you’ll note intermediate files such as the frameworks are all built in the sample app.

If you drag the needed frameworks into your own app, Xcode will put them in the right place in your project.

You can add new frameworks and functionality to your Facebook app either at the beginning or at any time as you work with the app. The My Apps menu in the navigator at the top of the screen (seen in Figure 7-10) lets you both add and reconfigure your app’s components.

From your app dashboard (Figure 7-10) you can choose new products (features), as shown in Figure 7-11. This display shows you available products and links to specific documentation so you can decide what you want to work on.

Enhancing Your App

If you have followed along with this chapter, you have produced the app shown previously in Figure 7-3. It runs and displays its storyboard, which happens to be blank. In order to move forward, it makes sense to add something to your storyboard.

Go to main.storyboard in your app and add a label to it, as you can see in Figure 7-12.

Next, add a Facebook login button to your app. If you have followed the sequence shown previously in which you built the SwitchUserSample example, you have the Facebook Login framework in that app and you can drag it into your new app. Alternatively, add Facebook Login from the products shown in Figure 7-11 by modifying one of your apps (shown in My Apps in Figure 7-10).

Once Facebook Login is added to your app, the code to add the button is simple. Add it to the viewDidLoad method of your app. (If it’s built on the SingleViewController template as described in this chapter, the app has one view controller called ViewController.

The code is shown in Figure 7-13 and in Listing  7-1.

Rebuild your app (clean the build files first to make certain that you don’t have some experiments lying around). Now, when you run it, you should see your label and the button, as shown in Figure 7-14.

Remember that you didn’t just add the image of a button: you added the functionality of the login button, so when you run your app you’ll be asked for permission, as you can see in Figure 7-15.

The login button should work now. Try it, as shown in Figure 7-16.

You can also test with your own Facebook account. In addition, you can search developers.facebook.com to get test accounts you can use so that you don’t create fake accounts or interfere with your own account.

Summary

This has been an overview of integrating Facebook and iOS. The details may change from time to time, but the overview remains basically the same. And, in fact, it’s the same for all components of Facebook and other frameworks that you may want to integrate with your app.