Apple App Development with Swift App-Development-with-Swift-Certified-User Apple Study Notes

This question belongs to View Building with SwiftUI , specifically the objective on positioning and laying out a single SwiftUI view with standard views and modifiers.

The correct answer is D because it uses the right combination of SwiftUI image modifiers for all three requirements:

the image is made resizable with .resizable()

it is given rounded corners with .clipShape(RoundedRectangle(cornerRadius: 50))

it displays the entire image with .aspectRatio(contentMode: .fit)

it is sized with .frame(width: 300)

The key part is .aspectRatio(contentMode: .fit) . In SwiftUI, .fit scales the image so the whole image remains visible inside the available frame. That matches the requirement “displays the entire image, regardless of size.” By contrast, .fill may crop part of the image, so options using .fill do not satisfy the requirement.

Why the others are wrong:

Option A uses .fill, so the full image may not remain visible.

Option B uses invalid modifiers such as .sizablc() and .size(width: 300), and also uses Rectangle(cornerRadius: 50), which is not the correct rounded-rectangle shape syntax.

Option C also uses invalid syntax and .fill, which can crop the image.

Option D uses valid SwiftUI syntax and the correct content mode.

So the correct choice is D , because it is the only option that correctly creates a 300-width image with rounded corners while ensuring the entire image is shown.

This question belongs to View Building with SwiftUI , specifically the domain on creating a multi-view app with navigation stacks, links, and sheets .

To present a modal view in SwiftUI when a Boolean state changes, the correct modifier is .sheet . The matching sheet API for a Boolean binding is:

sheet(isPresented: $showInfo) {

// modal content

}

So the first blank must be .sheet , and the second blank must be (isPresented: .

The logic works like this:

@State stores the local Boolean that controls presentation.

Pressing the button calls showInfo.toggle(), changing the value from false to true.

When that Boolean becomes true, the .sheet(isPresented:) modifier presents the modal view.

When the modal is dismissed, SwiftUI updates the Boolean back as needed.

There is also a typing issue in the screenshot: the state variable appears as ShowInfo, while the button and binding use showInfo. Swift is case-sensitive, so those names must match. The corrected code should use the same identifier consistently, such as:

@State var showInfo = false

Therefore, the correct dropdown selections are:

sheet

(isPresented:

This question belongs to View Building with SwiftUI , especially the domain on creating multiple views to implement app logic and sharing values between views. In FirstView, the value typed into the TextField is stored in number, which is a String. When the NavigationLink is tapped, the code passes Int(number) ?? 0 into SecondView. In Swift, converting a string to an integer with Int(...) uses an optional initializer, which means it returns an optional value and will produce nil if the string cannot be converted. The ?? 0 nil-coalescing operator then supplies 0 if conversion fails.

Inside SecondView, the body is:

Color(passedNumber == 3 ? .blue : .red)

This uses the ternary conditional operator. If passedNumber equals 3, the displayed color is blue; otherwise, it is red. Therefore, entering 3 into the TextField causes Int(number) to become 3, which makes the condition passedNumber == 3 true and displays a blue canvas. Any other listed number results in red.

So the correct answer is A. 3 . This matches the SwiftUI pattern of taking user input, converting it to the needed type, passing it into another view, and rendering UI conditionally based on that value.