Fragment Within A Fragment or ListActivity Within A Fragment?

Question

I use the following to select which fragment to display within my activity....

    public class SectionsPagerAdapter extends FragmentPagerAdapter {

    public SectionsPagerAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int position) {

        Fragment fragment;
        switch (position) {
        case 0:
            fragment = new Fragment1();
            break;
        case 1:
            fragment = new Fragment2();
            break;
        case 2:
            fragment = new Fragment3();
            break;
        default:
            fragment = null;
            break;
        }
        return fragment;

    }

... a blank and working fragment looks like....

public class Fragment2 extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View root = inflater.inflate(R.layout.fragment_dod, container, false);
// Do Stuff Here
        return root;
    }

    @Override public void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        // Save some state!
      }
}

How ever my SectionsPagerAdapter errors with type mismatch: cannot convert from Fragment2 to Fragment when using a ListFragment like the following.....

public class Fragment2 extends ListFragment {
  DemoAdapter adapter=null;

  @Override
  public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);

    setRetainInstance(true);

    if (adapter==null) {
      ArrayList<Integer> items=new ArrayList<Integer>();

      for (int i=0;i<25;i++) { items.add(i); }

      adapter=new DemoAdapter(getActivity(), items);
    }
    else {
      adapter.startProgressAnimation();
    }

    setListAdapter(adapter);
  }
}

I have been looking for a way to get round this. Could some one advise a way to do so and if possible an explanation so I understand why and can try and avoid it in the future ?

Thanks

Answer 1

The answer to my problem can be found here - Why can't I instantiate this Fragment on Android?

Figured out the issue.... my MainActivity.java file was using:

import android.support.v4.app.Fragment; and my MainFragment.java file was using:

import android.app.Fragment; So there was a mismatch. I am using ICS 4.0 and higher as my lowest API version. Changing everything to import to the v4 API solved my issue