====== アクティビティのライフサイクル ======

[[https://developer.android.com/reference/android/app/Activity.html?hl=ja#ActivityLifecycle|Activity]]

===== mainの起動 =====
Main onCreate is called!!
Main onStart is called!!
Main onResume is called!!

===== mainからsubの呼び出し =====
Main onPause is called!!
Sub onCreate is called!!
Sub onStart is called!!
Sub onResume is called!!
Main onStop is called!!

===== subが表示している状態で□ボタン =====
Sub onPause is called!!
Sub onStop is called!!

そのままアプリを選択して戻る
Sub onStart is called!!
Sub onResume is called!!

===== subが表示している状態でホームボタン（○） =====
Sub onPause is called!!
Sub onStop is called!!

そして再度アプリ起動
Sub onStart is called!!
Sub onResume is called!!

===== subが表示している状態で戻るボタン（◁） =====
Sub onPause is called!!
Main onStart is called!!
Main onResume is called!!
Sub onStop is called!!
Sub onDestroy is called!!

===== subが表示している状態でボタンでfinish() =====
Sub onPause is called!!
Main onStart is called!!
Main onResume is called!!
Sub onStop is called!!
Sub onDestroy is called!!

===== mainが表示している状態でホームボタン =====
Main onPause is called!!
Main onStop is called!!

そして再度アプリ起動
Main onStart is called!!
Main onResume is called!!

===== mainが表示している状態で戻るボタン =====
Main onPause is called!!
Main onStop is called!!
Main onDestroy is called!!


===== 自動終了 =====

2019-10-18 06:07:09.878 4535-4535/? D/service: onStartCommand is called
2019-10-18 06:07:09.890 4535-4535/? D/service: setOnPreparedListener is called
2019-10-18 06:07:15.417 4535-4535/? D/service: setOnCompletionListener is called
2019-10-18 06:07:15.419 4535-4535/? D/service: onDestroy is called

===== 停止した場合 =====

2019-10-18 06:07:39.078 4535-4535/? D/service: onStartCommand is called
2019-10-18 06:07:39.089 4535-4535/? D/service: setOnPreparedListener is called
2019-10-18 06:07:39.892 4535-4535/? D/service: onDestroy is called