iOS Development IOS App Development Fundamentals 5

Question 1

Which Apple framework provides a declarative API for processing values over time with publishers and subscribers?

Accepted Answer

Combine

Answer

Combine is a reactive framework that handles asynchronous events using publishers and subscribers.

Question 2

What does ARC (Automatic Reference Counting) manage in Swift?

Accepted Answer

Memory by tracking object references

Answer

ARC automatically tracks and frees memory used by class instances when no references remain.

Question 3

What problem does a 'weak' reference help prevent in Swift?

Accepted Answer

Retain cycles (strong reference cycles)

Answer

A weak reference avoids retain cycles by not increasing the reference count of the referenced object.

Question 4

In Swift concurrency, which keyword marks a function that can be awaited?

Accepted Answer

async

Answer

The 'async' keyword marks a function as asynchronous so it can be paused and awaited.

Question 5

Which property wrapper observes an external reference-type model and is owned by the view in SwiftUI?

Accepted Answer

@StateObject

Answer

@StateObject creates and owns an observable reference-type object, keeping it alive across view updates.

iOS Development Practice Test