Android中的活动/片段模式

Question

I've a activity which basically is :

public class FragmentContainer extends FragmentActivityBase implements IRefreshListener {
    public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);

            if (getIntent().getExtras() == null
                    || getIntent().getExtras().get("type") == null) {

              showProductList();
            }
            else
            {
            if (getIntent().getExtras().get("type").equals("customer"))
                    showCustomerList();
    }

    @Override
    public void showProductList() {
        FragmentManager fragmentManager = getSupportFragmentManager();
        FragmentTransaction fragmentTransaction = fragmentManager
                .beginTransaction();

        // load the product list
        ProductList fragment = new ProductList();

        fragmentTransaction.replace(R.id.fragment_container, fragment)
                .addToBackStack(null);
        fragmentTransaction.commit();
    }

    .....
}

in the fragment, I use onCreateView to get intent and then I create my view. If I need to change the fragment, I get the reference to the parent Activity (taken from onAttach) and I call method referenced by the IRefreshListener.

like :

IRefreshListener mCallback;

@Override
public void onAttach(Activity activity) {
    super.onAttach(activity);

    // This makes sure that the container activity has implemented
    // the callback interface. If not, it throws an exception.
    try {
        mCallback = (IRefreshListener) activity;
    } catch (ClassCastException e) {
        throw new ClassCastException(activity.toString()
                + " must implement IRefreshListener");
    }
}


public void callCustomer() {
  mCallback.showCustomerList();
}

It works but whne I change the orientation, even I use setRetainInstance(true) it will be reseted.

I have 2 questions :

1. Do I use the good pattern to manage my application. The big activity which contains one fragment become bigger with the time
2. How should I handle orientation change ?

Regards

Answer 1

I do not find this pattern is more perfect or best one, although it is or was a suggestion from Google. Because it could be a worse coding style if fragment knows particular activity or listeners, you might write more and more code, when you wanna to let your fragment know more its "container" or "parents". Will the fragment later be used for other activity which has not been implemented with IRefreshListener etc, you will code much more.

My introduce is using Otto-Bus or Event-Bus. You can just send message from one to one. Every one doesn't have to know each other.