import android.os.Bundle;
import android.app.Activity;
import android.app.ListFragment;
import android.app.Fragment;
import android.app.FragmentTransaction;
import android.support.v4.app.FragmentActivity;
import android.view.Menu;

public class MainActivity extends FragmentActivity implements LeftFragment.OnListSelectedListener {


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        if (findViewById(R.id.left_pane)!=null){
            if(savedInstanceState!=null){


                return;
        }

        LeftFragment leftfragment = new LeftFragment();

        leftfragment.setArguments(getIntent().getExtras());

        getSupportFragmentManager().beginTransaction()
        .commit();

        }
    }
    public void onListSelected(int position){

                DetailFragment detailfrag=(DetailFragment).getFragmentManager().findFragmentById(R.id.content_pane);
                if(detailfrag!=null){
            detailfrag.updateDetailFragment(position);
        }else{
            DetailFragment newfragment = new DetailFragment();
            Bundle args = new Bundle();
            args.putInt(DetailFragment.ARG_POSITION, position);
            newfragment.setArguments(args);
            FragmentTransaction transaction = getFragmentManager().beginTransaction();

            transaction.replace(R.id.content_pane, newfragment);
            transaction.addToBackStack(null);
            transaction.commit();
        }
    }


}