What Is The Most Suitable Way To Store Object In Android?

Hello in my app I need to store single object with several fields. At this moment it is saved like this @Override public Object onRetainNonConfigurationInstance() { re

Solution 1:

Taken from my calculator:

@SuppressWarnings("unchecked")
privatevoidloadState() {
    ObjectInputStream ois;
    try {
        ois = newObjectInputStream(openFileInput(FILE_STATE));
        state = ((State) ois.readObject());
        ois.close();

        ois = newObjectInputStream(openFileInput(FILE_HISTORY));
        historyListAdapter.setItems((List<String>) ois.readObject());
        ois.close();

    } catch (FileNotFoundException e) {
        e.printStackTrace();
        state = newState();
    } catch (IOException e) {
        e.printStackTrace();
        state = newState();
    } catch (ClassNotFoundException e) {
        Toast t = Toast.makeText(this, "Error parsing saved state",
                Toast.LENGTH_SHORT);
        t.show();
        state = newState();
    }
    setState(state);
}

privatevoidsaveState() {
    ObjectOutputStream oos;
    try {
        oos = newObjectOutputStream(openFileOutput(FILE_STATE,
                Context.MODE_PRIVATE));
        oos.writeObject(state);
        oos.close();

        oos = newObjectOutputStream(openFileOutput(FILE_HISTORY,
                Context.MODE_PRIVATE));
        oos.writeObject(historyListAdapter.getItems());
        oos.close();

    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

@OverrideprotectedvoidonPause() {
    saveState();
    super.onPause();
}

Call loadState() in onCreate().

Worked fine for me, I know its not advised to use java serialization in android, but I didn't encounter any errors or bugs whatsoever. No issues with performance either.

You should of course tweak error handling depending on your application.

Solution 2:

Depends how big your object is. Try with shared preferences: http://developer.android.com/guide/topics/data/data-storage.html#pref

Combination of preferences, right places to populate/read from it, and some static init method could do things for you.

Hope it helps.