Question

I have an ActionBar with List Navigation mode.
The problem is after selecting items from the navigation spinner, when the screen orientation changes the navigation spinner selected index is reset to 0.

How can I preserve the selected index of the spinner during configuration changes ?

Thanks

Answer 1

You should override onSaveInstanceState and save selected navigation list position to bundle.
Don’t forget to restore position in onCreate.

Look at example below:

public class MainActivity
{

    private static final String CURRENT_FRAGMENT_TAG = "fragmentPosition";

    @Inject @Named("navigationFragments")
    private Provider<? extends Fragment>[] fragmentProviders;

    @Override
    protected void onCreate(Bundle bundle)
    {
        super.onCreate(bundle);

        final ActionBar actionBar = getSupportActionBar();
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_LIST);
        actionBar.setListNavigationCallbacks(ArrayAdapter.createFromResource(
            this, R.array.navigation_menu, android.R.layout.simple_list_item_1), new ActionBar.OnNavigationListener()
        {
            @Override
            public boolean onNavigationItemSelected(int itemPosition, long itemId)
            {
                final String fragmentTag = "fragment-" + itemPosition;

                // to prevent fragment re-selection and loosing early saved state
                if (getSupportFragmentManager().findFragmentByTag(fragmentTag) != null)
                {
                    return true;
                }

                final Fragment fragment = fragmentProviders[itemPosition].get();
                getSupportFragmentManager().beginTransaction().
                    replace(android.R.id.content, fragment, fragmentTag).
                    commit();
                return true;
            }
        });
        actionBar.setSelectedNavigationItem(bundle != null
            ? bundle.getInt(CURRENT_FRAGMENT_TAG)
            : 0);
    }

    @Override
    protected void onSaveInstanceState(Bundle outState)
    {
        super.onSaveInstanceState(outState);
        outState.putInt(CURRENT_FRAGMENT_TAG, getSupportActionBar().getSelectedNavigationIndex());
    }

    /*

        Additional stuff here

     */

}

Provider<? extends Fragment>[] fragmentProviders is a list of factory method objects which creates new fragment.
Replace getSupportActionBar() to getActionBar() and getSupportFragmentManager() to getFragmentManager() if you don’t use actionbarsherlock