http://blog.synchack.com/2012/04/themerecreateclass.html

MainActivity.java

// SherlockFragmentActivityになってるけどActivityでも動作するよ
// MainActivityはHoneycombGalleryのまんま流用
public class MainActivity extends SherlockFragmentActivity implements
        TitlesFragment.OnItemSelectedListener {

    @Override
    public void onCreate(Bundle savedInstanceState) {

        if (savedInstanceState == null) {
            //追加箇所：RecreateActivityから呼び出された時の処理をしている
            Bundle recreateState = RecreateActivity.recreateBundle(getIntent());
            if (recreateState != null) {
                // オリジナルのコピペ。手抜きすぐるｗ
                if (recreateState.getInt("theme", -1) != -1) {
                    mThemeId = recreateState.getInt("theme");
                    this.setTheme(mThemeId);
                }
                mTitlesHidden = recreateState.getBoolean("titlesHidden");
            }
        } else {
            // オリジナル
            if (savedInstanceState.getInt("theme", -1) != -1) {
                mThemeId = savedInstanceState.getInt("theme");
                this.setTheme(mThemeId);
            }
            mTitlesHidden = savedInstanceState.getBoolean("titlesHidden");
        }

        // super.onCreateより上でsetThemeはよもや常識のバッドノウハウｗ
        // もうやだ
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        // 以下略
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        // 変更箇所：苦肉の策。onSaveInstanceStateで保存されるパラメータを共用
        addSaveInstanceState(outState);
    }

    // 追加箇所：パラメータの内容は素のままでOK
    private void addSaveInstanceState(Bundle outState) {
        outState.putInt("theme", mThemeId);
        outState.putBoolean("titlesHidden", mTitlesHidden);
    }

    // 追加箇所：むしゃくしゃしてたのでOverrideしたｗ
    @Override
    public void recreate() {

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
            // Android 3.x以上なら通常処理。念を入れるならrefrect処理も。
            super.recreate();
        } else {
            Bundle outState = new Bundle();
            addSaveInstanceState(outState);
            startActivity(RecreateActivity.recreateIntent(
                    getApplicationContext(),
                    getClass().getName(),
                    outState));
            overridePendingTransition(0, 0);
            finish();
            overridePendingTransition(0, 0);
        }
    }
}