CODEWITHSUNDEEP
androidandroid-savedstate
Wai Yan Hein
Wai Yan Hein

Reputation: 14771

Data from savedInstanceState is always empty in Android

I am developing an Android app. I am testing using onSaveInstanceState event in activity. But it is not working as I expected, because value string is always empty when I retrieve it back onCreate event.

This is my activity

@Override
    public void onSaveInstanceState(Bundle outState, PersistableBundle outPersistentState) {
        super.onSaveInstanceState(outState, outPersistentState);
        outState.putString("message","Hello world!");
    }

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    if(savedInstanceState!=null)
    {
        Toast.makeText(getBaseContext(),savedInstanceState.getString("message"),Toast.LENGTH_SHORT).show();
        //Log.i("DATA_FROM_STATE",savedInstanceState.getString("message"));
    }
}

When I run activity and change orientation, it is always toasting empty message. When I test uncommenting the Log line, it is giving me error because data string is empty or null. Why it is not working? How can I save and retrieve correctly?

Upvotes: 0

Views: 724

Answers (2)

Abdullah
Abdullah

Reputation: 965

At first glance I saw that your are calling super before you saved the data And I guess your app is running on API21+ version of Android, because it is needed to call your method

public void onSaveInstanceState (Bundle outState, PersistableBundle outPersistentState);

@Override
    public void onSaveInstanceState(Bundle outState,PersistableBundle outPersistentState) {
        outState.putString("message","Hello world!");
        super.onSaveInstanceState(outState, outPersistentState);

    }

Upvotes: 0

damjanh
damjanh

Reputation: 143

Wrong method override. Should use onSaveInstanceState(Bundle outState) and it will work. You can copy below snippet and test it.

public class MainActivity extends AppCompatActivity {

    private final String SAVED_MESSAGE_KEY = "SAVED_MESSAGE";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        if(savedInstanceState != null) {
            if(savedInstanceState.containsKey(SAVED_MESSAGE_KEY)) {
                Log.i("Saved message is:", savedInstanceState.getString(SAVED_MESSAGE_KEY));
            }
        }
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putString(SAVED_MESSAGE_KEY, "Hello world!");
    }
}

Upvotes: 1

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