Android Development Android Development 5

Question 1

Your app targets API 33+ and needs to show notifications. What must you do first?

Accepted Answer

Request the POST_NOTIFICATIONS runtime permission

Answer

Android 13 (API 33) introduced the POST_NOTIFICATIONS runtime permission, which users must grant before notifications appear.

Question 2

What is the main advantage of using ConstraintLayout over deeply nested LinearLayouts?

Accepted Answer

A flatter view hierarchy, which improves layout measurement performance

Answer

ConstraintLayout positions views with constraints in a single flat layer, avoiding costly nested measure passes.

Question 3

A QA engineer wants to test an Activity's UI interactions automatically on a device. Which framework is designed for this?

Accepted Answer

Espresso

Answer

Espresso drives and asserts on real UI components in instrumented tests running on a device or emulator.

Question 4

What happens to an app's process when the system is low on memory and the app is in the background?

Accepted Answer

The system may kill the process, and saved instance state helps restore the UI later

Answer

Android reclaims memory by killing background processes, so apps must save state to restore correctly on return.

Question 5

In Kotlin, what does a 'sealed class' provide when modeling UI states like Loading, Success, and Error?

Accepted Answer

A restricted class hierarchy enabling exhaustive when-expression handling

Answer

Sealed classes limit subclasses to a known set, so a when expression can be checked for exhaustiveness at compile time.

Android Development Practice Test