SwiftUI SwiftUI State and Data Flow 2

Question 1

How do you pass an `@EnvironmentObject` to a child view?

Accepted Answer

Use `.environmentObject()` modifier on the parent view

Answer

You inject the object into the environment using `.environmentObject()`, making it available to all descendant views.

Question 2

What happens to a `@State` variable when a SwiftUI view is destroyed and recreated?

Accepted Answer

It resets to its initial value

Answer

SwiftUI resets `@State` to its initial value each time the view's identity changes and it is recreated.

Question 3

Which property wrapper reads a value from SwiftUI's environment without requiring it to be an ObservableObject?

Accepted Answer

@Environment

Answer

`@Environment` reads values from the environment using a key path, such as `\.colorScheme` or `\.locale`.

Question 4

What is the purpose of `@AppStorage` in SwiftUI?

Accepted Answer

Provides a binding to a UserDefaults key

Answer

`@AppStorage` wraps UserDefaults, automatically updating the view when the stored value changes.

Question 5

How do you create a `Binding` value manually in SwiftUI?

Accepted Answer

Both A and B are valid for different purposes

Answer

You can create a custom Binding with get/set closures or use `Binding.constant()` for a read-only binding in previews.

SwiftUI Practice Test