Question

For online games, it would be great to know if an Android Activity‘s onDestroy() is only called because Android is going to re-create it (e.g. device rotation) or if the user opted to exit the game.

My plan was to set a flag in the Activity‘s onSaveInstanceState() when Android is probably re-creating the Activity:

private boolean mDestroyedForReCreation;
...
protected void onSaveInstanceState() {
    ...
    mDestroyedForReCreation = true;
}

If you did this, you can check mDestroyedForReCreation in onDestroy():

• If the flag is set (true), don’t dismiss the user from the online game.
• If the flag is not set (false), dismiss the user from the online game as he did voluntarily exit the game.

Is that a correct approach? And if yes, is it recommended or is there any better solution? I hope so because I don’t really like that solution …

Answer 1

I suggest you to remove such kind of game logic from activity’s life cycle. Create a Service. If no one binded – all activities are dead. Is someone binded – keep working.

If you do not want to create service, you can use onRetainNonConfigurationInstance method. Here is example.

You should use onRetainNonConfigurationInstance because it is called by the system, as part of destroying an activity due to a configuration change, when it is known that a new instance will immediately be created for the new configuration. onSaveInstanceState called when android going to kill activity and maybe restore it sometimes or maybe not ).