Order the steps
Order the callbacks when an app is opened from the launcher and then sent home.
Choose an answer, then open Show answer below to check it.
Answer: B C A D E
onCreate sets up the UI and reads saved state. onStart means visible; onResume means in front and taking input. onPause means losing focus, which also happens in multi-window or when a dialog-style Activity appears. onStop means no longer visible, and onDestroy means finishing or being recreated. Keep onPause fast; save work in onStop or continuously.
Explain the Activity lifecycle.
Say your answer out loud, then check which of these points you covered:
In multi-window on Android 10 and later, every visible Activity is resumed; the one with focus is reported by onTopResumedActivityChanged. Tie visibility-based work to start/stop.
isFinishing and isChangingConfigurations tell you why onDestroy is called.
onSaveInstanceState runs after onStop on Android 9 and later.
Lifecycle-aware components (DefaultLifecycleObserver, repeatOnLifecycle) keep this logic out of the Activity.
onPause, which delays the next Activity.onDestroy is always called; the process can be killed without it.onResume without stopping it.Pair the callbacks (create/destroy, start/stop, resume/pause) and say what each pair means: created, visible, in front.
Think of your answer first, then open the hint.
When is onDestroy not called?
When the system kills the process, for example in the background.
Why is onPause kept short?
The next Activity's onResume waits for it.
Similar on iOS: App and scene lifecycle states iOS has scene states (active, inactive, background) rather than per-screen callbacks.
Suggest a fix if something here is wrong or out of date.