Sample questions
Mobile Ui LifecycleDifficulty 1
In mobile app lifecycle terms, what does "foreground" state mean?
- aThe process exists but has no window at all
- bVisible and actively receiving user input✓
- cThe process has been fully removed from memory
- dThe app is still compiling before first launch
Explanation:Foreground means the app's UI is on screen and receiving user input, as opposed to background (not visible but process alive) or terminated (process gone).
Mobile Ui LifecycleDifficulty 2
A user presses the home button while a screen is open. What generally happens to the app's process right after?
- aIt is guaranteed to terminate within a second
- bIt restarts from scratch on the next home tap
- cIt is forced to crash to free memory
- dIt backgrounds and stays alive until the OS reclaims it✓
Explanation:Pressing home typically backgrounds the app; the process keeps running (possibly with restrictions) until the operating system needs the memory and decides to terminate it.
Mobile Ui LifecycleDifficulty 2
An app holds an open camera while the user is on that screen. Why release the camera when going to background?
- aBackground apps usually can't use it; holding it wastes battery✓
- bCameras shut off at hardware level automatically
- cReleasing it is purely cosmetic, no real effect
- dCamera access is unrelated to lifecycle at all
Explanation:Sensitive hardware resources (camera, sensors) should be released on backgrounding because a backgrounded app usually cannot use them anyway, and holding them wastes battery and can block other apps.
Mobile Ui LifecycleDifficulty 1
What is "state restoration" in the context of app lifecycle?
- aRecompiling the source code after an update
- bResetting all preferences to factory defaults
- cRestoring screen/data after relaunch✓
- dAutomatically logging the user out
Explanation:State restoration means bringing the UI back to where the user left off (same screen, scroll position, entered data) after the app process was relaunched, typically after being killed by the system.
Mobile Ui LifecycleDifficulty 2
From the user's view, what is the key practical difference between a backgrounded app and a terminated one?
- aNo observable difference in any situation
- bBackgrounded resumes instantly, terminated must rebuild state✓
- cTerminated keeps network requests running, backgrounded does not
- dBackgrounded always loses form input, terminated never does
Explanation:A backgrounded process still has its memory (variables, view state) intact, so returning to it is instant. A terminated app has no process left, so relaunching means rebuilding everything from scratch (plus any restored state).
Mobile Ui LifecycleDifficulty 2
Screen lifecycle events fire in a guaranteed order (e.g. "about to lose focus" before "entered background"). Why does this matter?
- aCleanup fits reliably at the right stage✓
- bIt only matters for automated UI testing tools
- cIt guarantees the app is never terminated
- dIt removes any need to release resources
Explanation:Because the framework guarantees a fixed event order, developers can put specific cleanup or save logic in the right callback and trust it always runs before the next stage, instead of guessing or racing.