NavigationLink in iOS Swift - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a NavigationLink with a text label.

iOS Swift

NavigationLink(destination: Text("Detail View")) {
    Text([1])
}

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

Adestination

B"Go to Detail"

C"Button"

DDetailView()

Attempts:

3 left

💡 Hint

Common Mistakes

Using a view instead of a string inside Text.

Forgetting quotes around the string.

The label inside NavigationLink is a Text view showing "Go to Detail".

2fill in blank

medium

Complete the code to navigate to a custom view called DetailView.

iOS Swift

NavigationLink(destination: [1]) {
    Text("Show Detail")
}

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

A"DetailView"

BText("Detail")

CDetailView()

DNavigationView()

Attempts:

3 left

💡 Hint

Common Mistakes

Passing a string instead of a view instance.

Passing a view type without parentheses.

The destination must be a view instance, so use DetailView() to navigate to that view.

3fill in blank

hard

Fix the error in the NavigationLink label to correctly display text.

iOS Swift

NavigationLink(destination: DetailView()) {
    [1]("Go")
}

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

ANavigationLink

BButton

CLabel

DText

Attempts:

3 left

💡 Hint

Common Mistakes

Using Button inside NavigationLink label causing nested buttons.

Using NavigationLink inside its own label.

The label inside NavigationLink should be a Text view to display the string "Go".

4fill in blank

hard

Fill both blanks to create a NavigationLink with a label and destination view.

iOS Swift

NavigationLink(destination: [1]) {
    [2]("Next Screen")
}

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

ANextView()

BText

CDetailView()

DButton

Attempts:

3 left

💡 Hint

Common Mistakes

Using Button as label inside NavigationLink.

Passing a string instead of a view as destination.

The destination is DetailView() and the label is a Text view showing "Next Screen".

5fill in blank

hard

Fill all three blanks to create a NavigationLink with a destination and a label showing an image and text.

iOS Swift

NavigationLink(destination: [1]) {
    HStack {
        Image(systemName: [2])
        Text([3])
    }
}

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

ASettingsView()

B"gearshape"

C"Settings"

DProfileView()

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting quotes around image systemName or text string.

Using wrong view as destination.

The destination is SettingsView(), the image uses systemName "gearshape", and the label text is "Settings".

Practice

1. What is the main purpose of NavigationLink in SwiftUI?

easy

A. To display images in a grid layout

B. To create a tappable item that opens a new screen

C. To fetch data from the internet

D. To style text with colors and fonts

Solution

1. Step 1: Understand NavigationLink role

   NavigationLink is used to create tappable items that navigate to another view.

2. Step 2: Compare other options

   Options A, B, and C describe unrelated tasks like styling, fetching data, or layout.

3. Final Answer:

   To create a tappable item that opens a new screen -> Option B

4. Quick Check:

   NavigationLink = tappable navigation [OK]

Hint: NavigationLink always creates tappable navigation items [OK]

Common Mistakes:

• Confusing NavigationLink with styling or data fetching
• Thinking NavigationLink displays images only
• Assuming NavigationLink is for layout purposes

2. Which of the following is the correct syntax to create a NavigationLink with a text label "Next" that opens DetailView()?

easy

A. NavigationLink(destination: Text("Next")) { DetailView() }

B. NavigationLink(destination: Text("Next"), DetailView())

C. NavigationLink { DetailView() } label: { Text("Next") }

D. NavigationLink(destination: DetailView()) { Text("Next") }

Solution

1. Step 1: Recall NavigationLink syntax

   The correct syntax uses NavigationLink(destination: View) { LabelView }.

2. Step 2: Check each option

   NavigationLink(destination: DetailView()) { Text("Next") } matches the correct syntax. NavigationLink(destination: Text("Next"), DetailView()) swaps parameters incorrectly. NavigationLink { DetailView() } label: { Text("Next") } uses a newer syntax and is valid in SwiftUI 3+, so it is also correct. NavigationLink(destination: Text("Next")) { DetailView() } swaps destination and label views wrongly.

3. Final Answer:

   NavigationLink(destination: DetailView()) { Text("Next") } -> Option D

4. Quick Check:

   Correct parameter order = NavigationLink(destination: DetailView()) { Text("Next") } [OK]

Hint: Destination first, label inside closure for NavigationLink [OK]

Common Mistakes:

• Swapping destination and label parameters
• Using incorrect closure syntax
• Passing views in wrong order

3. What will happen when the user taps the text "Go to Profile" in this SwiftUI code?

NavigationView {
  NavigationLink(destination: ProfileView()) {
    Text("Go to Profile")
  }
}

medium

A. The app navigates to ProfileView screen

B. Nothing happens because NavigationView is missing

C. The text changes color but no navigation occurs

D. The app crashes due to missing NavigationLink label

Solution

1. Step 1: Identify NavigationView and NavigationLink usage

   The code wraps NavigationLink inside NavigationView, enabling navigation.

2. Step 2: Understand tap behavior

   Tapping the text triggers navigation to ProfileView as destination is set.

3. Final Answer:

   The app navigates to ProfileView screen -> Option A

4. Quick Check:

   NavigationView + NavigationLink = navigation works [OK]

Hint: NavigationLink inside NavigationView enables screen navigation [OK]

Common Mistakes:

• Forgetting NavigationView disables navigation
• Thinking tap only changes text color
• Assuming app crashes without label

4. Identify the error in this SwiftUI code snippet:

NavigationLink(destination: Text("Details"))
Text("Tap here")

medium

A. Missing braces {} around the label view

B. Destination cannot be a Text view

C. NavigationLink must be inside a NavigationView

D. Text("Tap here") should be inside destination

Solution

1. Step 1: Check NavigationLink syntax

   NavigationLink requires a closure with braces {} for the label view.

2. Step 2: Analyze given code

   The label Text("Tap here") is outside NavigationLink without braces, causing syntax error.

3. Final Answer:

   Missing braces {} around the label view -> Option A

4. Quick Check:

   Label must be inside braces {} [OK]

Hint: Label view must be inside braces {} after NavigationLink [OK]

Common Mistakes:

• Omitting braces for label view
• Thinking destination can't be Text
• Assuming NavigationView is mandatory for syntax

5. You want to create a list of items where each item navigates to a detail screen showing that item's name. Which code correctly uses NavigationLink inside a List to achieve this?

hard

A. ForEach(items) { NavigationLink(destination: DetailView(name: $0)) { Text($0) } }

B. List { NavigationLink(Text(item), destination: DetailView(name: item)) }

C. List(items, id: \.self) { item in NavigationLink(destination: DetailView(name: item)) { Text(item) } }

D. List(items) { item in NavigationLink { Text(item) } destination: { DetailView(name: item) } }

Solution

1. Step 1: Understand List with NavigationLink

   Use List with identifiable items and NavigationLink inside closure for each item.

2. Step 2: Check each option's correctness

   List(items, id: \.self) { item in NavigationLink(destination: DetailView(name: item)) { Text(item) } } correctly uses List with id and NavigationLink with destination and label. List { NavigationLink(Text(item), destination: DetailView(name: item)) } has wrong parameter order. ForEach(items) { NavigationLink(destination: DetailView(name: $0)) { Text($0) } } uses ForEach but misses id and may cause errors. List(items) { item in NavigationLink { Text(item) } destination: { DetailView(name: item) } } uses invalid syntax for NavigationLink.

3. Final Answer:

   List(items, id: \.self) { item in NavigationLink(destination: DetailView(name: item)) { Text(item) } } -> Option C

4. Quick Check:

   List + NavigationLink with destination and label = List(items, id: \.self) { item in NavigationLink(destination: DetailView(name: item)) { Text(item) } } [OK]

Hint: Use List with id and NavigationLink inside closure [OK]

Common Mistakes:

• Wrong parameter order in NavigationLink
• Missing id in List or ForEach
• Using invalid NavigationLink syntax