Welcome to our workshop! Today, we are going to create a nonsense generator. The app is simple, yet covers many fundamental concepts all app developers need to know.

If you're worried about prerequisites, you probably shouldn't be. All you need is knowledge about some basic programming concepts, like loops and objects.

1. We hand out the Swift cheat sheet.
2. A short presentation that briefly covers:
   • Native vs. cross-platform app development
   • iOS app architecture
   • The View Controller life cycle
   • Programming in Swift
3. A live coding session, where we recreate the master branch's Xcode project. The goal of this part is that you will become confident to start developing.
4. A problem-solving session, where you will continue the development of the app. This is where we think you will learn the most. When you get stuck, we'll gladly help.

To develop iOS apps, you need a Mac with Xcode installed. Installing Xcode is fairly straight forward:

1. Search for Xcode on your Mac's App Store.
2. Click Install.
3. Once the installation is finished, open Xcode. When prompted with a dialog asking you to Install required components, choose Yes.

Currently, our app displays "..." instead of generated nonsense when it starts up. Modify the code so that it generates a sentence before the app is visible.

Hint: Copy-paste a line into the viewDidLoad method.

The UIViewController life cycle tells us that the UIViewController.viewDidLoad method is called when its view property has been loaded. That is just after the nonsenseLabel's text is set to "...", and is therefore the perfect spot to override it.

Change the viewDidLoad method to:

override func viewDidLoad() {
    super.viewDidLoad()

    updateNonsenseLabel()
}

Our app looks kind of boring. Make it shine using Interface Builder.

Hint: Open Main.storyboard, and the Attributes inspector (needle icon) in the right pane. Change colors, fonts, font sizes and more!

Few great apps have only one page (or View Controller)! But before we can add another, we need something to manage our View Controllers: a Navigation Controller.

Embed our View Controller in a Navigation Controller.

Select our View Controller in the Document Outline (the rightmost of the two left sidebars). In the Xcode menu, choose Editor -> Embed In -> Navigation Controller. Remember to run the app to see the changes!

If you ran the app, you probably noticed our View Controller got a top bar. What you see is its Navigation Item property. It is commonly used for displaying a title and some easily accessible buttons.

Set a title for the Navigation Item. Then, add a Bar Button Item to it.

Hint: Set the title in the Attributes Inspector. Add the Bar Button Item from the Object library.

To add a title, select the Navigation Item in the Document Outline, and edit its Title field from the Attributes Inspector. Set it to "Nonsense Generator" or something else.

To add a Bar Button Item, search for "button" in the Object library (lower right corner). Drag a Bar Button Item to the right side of our View Controller's Navigation Item, in the Storyboard. From the Attributes Inspector, change its Title property to "About".

It's time to add our second View Controller. From the Object library, drag a View Controller onto our Storyboard. From the Document Outline, name it About View Controller.

Then, add a segue of type Show from the View Controller's About button to the About View Controller.

Run the app and tap our new About button!

Hint: Right-click-and-drag in our Storyboard.

First, add the About View Controller as described in the exercise.

Then, right-click-and-drag from the About button in our original View Controller's Navigation Item, to the About View Controller. When you let go of the cursor, a black pop-up will appear. Choose Show under Action Segue.

We just added a new page to our app, but it looks very blank! Add something to it. Maybe a Label or Image View from the Object library?

We have supplied some app icons in the repo's App Icons directory. Add an app icon to the Assets.xcassets folder in Xcode.

In Xcode's Project navigator (folder icon in left pane), click on Assets.xcassets. Then, drag the app icons from the repo's App Icon directory to the icon placeholders.

For the app icon to be visible in the simulator, you need to add at least the "iPhone App" icons.

It should look something like this:

Now it's time to utilize the mysterious AppDelegate.swift. This file contains methods similar to those in the View Controller life cycle, but instead of belonging to a View Controller, they are system-wide.

Modify the app so that it generates new nonsense when the user leaves the app and then opens it again.

Hints: You'll want to put some code in applicationWillEnterForeground. To get our AppDelegate instance from the View Controller, use UIApplication.shared.delegate as! AppDelegate.

Gaute Solheim

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