Kotlin Kotlin Android Development 2

Question 1

What is `remember` used for in Jetpack Compose?

Accepted Answer

Preserving a value across recompositions

Answer

`remember` stores a value in composition memory so it survives recompositions, but is reset if the composable leaves the composition.

Question 2

What is `mutableStateOf` in Jetpack Compose?

Accepted Answer

A state holder that triggers recomposition when its value changes

Answer

`mutableStateOf` creates an observable state object; when its value changes, Compose schedules a recomposition of composables reading the state.

Question 3

Which Kotlin library is commonly used for dependency injection in Android apps?

Accepted Answer

Hilt

Answer

Hilt is the recommended dependency injection library for Android, built on top of Dagger and integrated with Android lifecycle components.

Question 4

What is Retrofit used for in Android Kotlin development?

Accepted Answer

A type-safe HTTP client for making network requests

Answer

Retrofit is a type-safe HTTP client for Android that converts REST API endpoints into Kotlin interface methods.

Question 5

What does `LaunchedEffect` do in Jetpack Compose?

Accepted Answer

Runs a suspend function in composition with a given key, relaunching when the key changes

Answer

`LaunchedEffect` runs a coroutine block tied to the composition lifecycle, cancelling and relaunching it when the specified key changes.

Kotlin Practice Test