Are fragments saved by default with savedInstanceState?

Question

I read on What's onCreate(Bundle savedInstanceState) that onsaveinstancestate gives you a bundle of the previous state of the application(if the orientation of the screen changed.

I looked on the Android docs(http://developer.android.com/training/basics/activity-lifecycle/recreating.html) and saw that you have to manually put the values you want saved as key value pairs. Their code for doing so was

    static final String STATE_SCORE = "playerScore";
static final String STATE_LEVEL = "playerLevel";
...

@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
    // Save the user's current game state
    savedInstanceState.putInt(STATE_SCORE, mCurrentScore);
    savedInstanceState.putInt(STATE_LEVEL, mCurrentLevel);

My question is for fragments, are they automatically reattached when the orientation changes and the activity recreated? Would you have to put code to save it into a bundle? Heres facebook code for this situation that I am trying to understand

 @Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

if (savedInstanceState == null) {
    // Add the fragment on initial activity setup
    mainFragment = new MainFragment();
    getSupportFragmentManager()
    .beginTransaction()
    .add(android.R.id.content, mainFragment)
    .commit();
} else {
    // Or set the fragment from restored state info
    mainFragment = (MainFragment) getSupportFragmentManager()
    .findFragmentById(android.R.id.content);
}

}

score 2 · Accepted Answer · answered Aug 19 '14 at 18:35

2

To keep a fragment when an Activity gets destroyed, so it automatically reataches, you should call

Fragment.setRetainInstance(true)

in the Fragment's constructor. Nothing is saved by default in onSaveInstanceState()

answered Aug 19 '14 at 18:35

Alexander Kulyakhtin

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So they are not by default retained? That's what I thought too. What do you mean by the constructor? Do you mean the oncreate lifecycle method? – committedandroider Aug 19 '14 at 18:37
No, I mean that Fragment's constructor. If you have setRetainInstance(true) in it and the Activity gets destroyed the Fragment won't be destroyed. – Alexander Kulyakhtin Aug 19 '14 at 18:37
https://developers.facebook.com/docs/android/login-with-facebook/v2.1#dialogs makes no mention of this at all in the fragment. Do you know why? – committedandroider Aug 19 '14 at 18:38
I don't but you can refer here http://developer.android.com/reference/android/app/Fragment.html#setRetainInstance(boolean) – Alexander Kulyakhtin Aug 19 '14 at 18:40

Are fragments saved by default with savedInstanceState?

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