Creating a new iOS project in iOS Swift - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a basic SwiftUI app entry point.

iOS Swift

import SwiftUI

@main
struct MyApp: App {
    var body: some Scene {
        WindowGroup {
            [1]()
        }
    }
}

Drag options to blanks, or click blank then click option'

ASceneDelegate

BAppDelegate

CContentView

DMainView

Attempts:

3 left

💡 Hint

Common Mistakes

Using AppDelegate or SceneDelegate here is incorrect because SwiftUI apps use a main view struct.

Using a name like MainView is possible but not the default in new projects.

The main view of a SwiftUI app is usually called ContentView. This is where the UI starts.

2fill in blank

medium

Complete the code to declare the main app struct conforming to the SwiftUI App protocol.

iOS Swift

import SwiftUI

@main
struct [1]: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

Drag options to blanks, or click blank then click option'

AMyApp

BMainApp

CAppMain

DSwiftApp

Attempts:

3 left

💡 Hint

Common Mistakes

Using generic names like AppMain or SwiftApp which are not default.

Using MainApp is possible but not the default.

The main app struct name is usually MyApp by default in new SwiftUI projects.

3fill in blank

hard

Fix the error in the code by completing the missing keyword to define the app's main entry point.

iOS Swift

import SwiftUI

[1]
struct MyApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

Drag options to blanks, or click blank then click option'

Aapp

B@main

C@UIApplicationMain

Dmain

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'main' without @ causes syntax error.

Using @UIApplicationMain is for UIKit apps, not SwiftUI.

The @main attribute tells Swift this is the app's entry point in SwiftUI.

4fill in blank

hard

Fill both blanks to complete the SwiftUI view struct with a Text label.

iOS Swift

import SwiftUI

struct ContentView: View {
    var body: some View {
        [1]("Hello, world!")
            .[2]()
    }
}

Drag options to blanks, or click blank then click option'

AText

Bpadding

Cframe

DButton

Attempts:

3 left

💡 Hint

Common Mistakes

Using Button instead of Text will change the UI behavior.

Using frame instead of padding changes layout differently.

The Text view shows text, and padding() adds space around it.

5fill in blank

hard

Fill all three blanks to create a SwiftUI app with a main struct, a ContentView, and a Text label.

iOS Swift

import SwiftUI

@[1]
struct [2]: App {
    var body: some Scene {
        WindowGroup {
            [3]()
        }
    }
}

struct ContentView: View {
    var body: some View {
        Text("Welcome to my app!")
    }
}

Drag options to blanks, or click blank then click option'

Amain

BMyApp

CContentView

DUIApplicationMain

Attempts:

3 left

💡 Hint

Common Mistakes

Using @UIApplicationMain instead of @main for SwiftUI apps.

Mixing up the app struct name and the view struct name.

The @main attribute marks the app entry. MyApp is the app struct name. ContentView is the main UI view.

Practice

1. What is the first step when creating a new iOS project in Xcode?

easy

A. Write Swift code immediately.

B. Open Xcode and select 'Create a new Xcode project'.

C. Download an app template from the App Store.

D. Connect your iPhone to the computer.

Solution

1. Step 1: Open Xcode

   You must start by opening Xcode, the tool used to build iOS apps.

2. Step 2: Choose to create a new project

   Selecting 'Create a new Xcode project' starts the setup wizard for your app.

3. Final Answer:

   Open Xcode and select 'Create a new Xcode project'. -> Option B

4. Quick Check:

   First step = Open Xcode and create new project [OK]

Hint: Always start by opening Xcode and creating a new project [OK]

Common Mistakes:

• Trying to write code before creating a project
• Downloading unrelated templates
• Connecting device before project setup

2. Which option correctly describes the interface style choices when creating a new iOS project?

easy

A. SwiftUI or Storyboard

B. UIKit or JavaFX

C. React Native or Flutter

D. XML or JSON

Solution

1. Step 1: Understand interface styles in Xcode

   Xcode offers SwiftUI and Storyboard as main interface design options for iOS apps.

2. Step 2: Identify correct pair

   SwiftUI is the modern declarative UI framework, Storyboard is the visual layout tool.

3. Final Answer:

   SwiftUI or Storyboard -> Option A

4. Quick Check:

   Interface style = SwiftUI or Storyboard [OK]

Hint: Remember: SwiftUI and Storyboard are Xcode's UI options [OK]

Common Mistakes:

• Confusing with unrelated frameworks like React Native
• Mixing UI frameworks from other platforms
• Choosing data formats instead of UI styles

3. After filling in the app name as "MyApp" and selecting SwiftUI, what will Xcode create?

medium

A. A Storyboard file without SwiftUI code

B. Only a blank text file named MyApp.txt

C. An Android app project

D. A project folder with SwiftUI files and a default ContentView.swift

Solution

1. Step 1: Understand project creation with SwiftUI

   Choosing SwiftUI creates a project folder containing SwiftUI code files.

2. Step 2: Identify default files

   Xcode generates ContentView.swift as the default UI file for SwiftUI projects.

3. Final Answer:

   A project folder with SwiftUI files and a default ContentView.swift -> Option D

4. Quick Check:

   SwiftUI project creates ContentView.swift file [OK]

Hint: SwiftUI projects always include ContentView.swift by default [OK]

Common Mistakes:

• Expecting unrelated file types
• Confusing iOS with Android projects
• Assuming Storyboard files appear with SwiftUI

4. You created a new project but forgot to select SwiftUI and chose Storyboard instead. What issue might you face?

medium

A. The app will crash immediately on launch.

B. Xcode will refuse to build the project.

C. Your UI code will use Storyboard files, not SwiftUI syntax.

D. You cannot add any UI elements later.

Solution

1. Step 1: Recognize interface style impact

   Choosing Storyboard means your UI is designed with Storyboard files, not SwiftUI code.

2. Step 2: Understand consequences

   This affects how you write UI code; you must use UIKit and Storyboard methods.

3. Final Answer:

   Your UI code will use Storyboard files, not SwiftUI syntax. -> Option C

4. Quick Check:

   Storyboard choice means no SwiftUI code [OK]

Hint: Storyboard projects use visual UI files, not SwiftUI code [OK]

Common Mistakes:

• Thinking the app will crash immediately
• Believing Xcode blocks building
• Assuming UI elements cannot be added later

5. You want to create an iOS app that supports both SwiftUI and UIKit views. How should you start your new project?

hard

A. Create a SwiftUI project and add UIKit views manually later.

B. Create a Storyboard project and convert it to SwiftUI automatically.

C. Create two separate projects, one for SwiftUI and one for UIKit.

D. Use a third-party tool to combine SwiftUI and UIKit automatically.

Solution

1. Step 1: Understand mixed UI support

   SwiftUI projects can embed UIKit views manually, allowing both UI styles.

2. Step 2: Choose best project start

   Starting with SwiftUI is easier; you can add UIKit views as needed.

3. Step 3: Evaluate other options

   Storyboard projects don't convert automatically; separate projects or tools are unnecessary.

4. Final Answer:

   Create a SwiftUI project and add UIKit views manually later. -> Option A

5. Quick Check:

   Start SwiftUI, add UIKit manually [OK]

Hint: Start SwiftUI project; add UIKit views manually if needed [OK]

Common Mistakes:

• Expecting automatic conversion from Storyboard to SwiftUI
• Creating two separate projects unnecessarily
• Relying on third-party tools for basic UI mixing